// Kludges for bugs and behavior differences that can't be feature
// detected are enabled based on userAgent etc sniffing.
var userAgent = navigator.userAgent
var platform = navigator.platform

var gecko = /gecko\/\d/i.test(userAgent)
var ie_upto10 = /MSIE \d/.test(userAgent)
var ie_11up = /Trident\/(?:[7-9]|\d{2,})\..*rv:(\d+)/.exec(userAgent)
var edge = /Edge\/(\d+)/.exec(userAgent)
var ie = ie_upto10 || ie_11up || edge
var ie_version = ie && (ie_upto10 ? document.documentMode || 6 : +(edge || ie_11up)[1])
var webkit = !edge && /WebKit\//.test(userAgent)
var qtwebkit = webkit && /Qt\/\d+\.\d+/.test(userAgent)
var chrome = !edge && /Chrome\//.test(userAgent)
var presto = /Opera\//.test(userAgent)
var safari = /Apple Computer/.test(navigator.vendor)
var mac_geMountainLion = /Mac OS X 1\d\D([8-9]|\d\d)\D/.test(userAgent)
var phantom = /PhantomJS/.test(userAgent)

var ios = !edge && /AppleWebKit/.test(userAgent) && /Mobile\/\w+/.test(userAgent)
var android = /Android/.test(userAgent)
// This is woefully incomplete. Suggestions for alternative methods welcome.
var mobile = ios || android || /webOS|BlackBerry|Opera Mini|Opera Mobi|IEMobile/i.test(userAgent)
var mac = ios || /Mac/.test(platform)
var chromeOS = /\bCrOS\b/.test(userAgent)
var windows = /win/i.test(platform)

var presto_version = presto && userAgent.match(/Version\/(\d*\.\d*)/)
if (presto_version) {
  presto_version = Number(presto_version[1])
}
if (presto_version && presto_version >= 15) {
  presto = false
  webkit = true
}
// Some browsers use the wrong event properties to signal cmd/ctrl on OS X
var flipCtrlCmd = mac && (qtwebkit || presto && (presto_version == null || presto_version < 12.11))
var captureRightClick = gecko || (ie && ie_version >= 9)

function classTest (cls) {
  return new RegExp('(^|\\s)' + cls + '(?:$|\\s)\\s*')
}

var rmClass = function (node, cls) {
  var current = node.className
  var match = classTest(cls).exec(current)
  if (match) {
    var after = current.slice(match.index + match[0].length)
    node.className = current.slice(0, match.index) + (after ? match[1] + after : '')
  }
}

function removeChildren (e) {
  for (var count = e.childNodes.length; count > 0; --count) {
    e.removeChild(e.firstChild)
  }
  return e
}

function removeChildrenAndAdd (parent, e) {
  return removeChildren(parent).appendChild(e)
}

function elt (tag, content, className, style) {
  var e = document.createElement(tag)
  if (className) {
    e.className = className
  }
  if (style) {
    e.style.cssText = style
  }
  if (typeof content === 'string') {
    e.appendChild(document.createTextNode(content))
  } else if (content) {
    for (var i = 0; i < content.length; ++i) {
      e.appendChild(content[i])
    }
  }
  return e
}

// wrapper for elt, which removes the elt from the accessibility tree
function eltP (tag, content, className, style) {
  var e = elt(tag, content, className, style)
  e.setAttribute('role', 'presentation')
  return e
}

var range
if (document.createRange) {
  range = function (node, start, end, endNode) {
    var r = document.createRange()
    r.setEnd(endNode || node, end)
    r.setStart(node, start)
    return r
  }
} else {
  range = function (node, start, end) {
    var r = document.body.createTextRange()
    try {
      r.moveToElementText(node.parentNode)
    } catch (e) {
      return r
    }
    r.collapse(true)
    r.moveEnd('character', end)
    r.moveStart('character', start)
    return r
  }
}

function contains (parent, child) {
  if (child.nodeType == 3) // Android browser always returns false when child is a textnode
  {
    child = child.parentNode
  }
  if (parent.contains) {
    return parent.contains(child)
  }
  do {
    if (child.nodeType == 11) {
      child = child.host
    }
    if (child == parent) {
      return true
    }
  } while (child = child.parentNode)
}

function activeElt () {
  // IE and Edge may throw an "Unspecified Error" when accessing document.activeElement.
  // IE < 10 will throw when accessed while the page is loading or in an iframe.
  // IE > 9 and Edge will throw when accessed in an iframe if document.body is unavailable.
  var activeElement
  try {
    activeElement = document.activeElement
  } catch (e) {
    activeElement = document.body || null
  }
  while (activeElement && activeElement.shadowRoot && activeElement.shadowRoot.activeElement) {
    activeElement = activeElement.shadowRoot.activeElement
  }
  return activeElement
}

function addClass (node, cls) {
  var current = node.className
  if (!classTest(cls).test(current)) {
    node.className += (current ? ' ' : '') + cls
  }
}

function joinClasses (a, b) {
  var as = a.split(' ')
  for (var i = 0; i < as.length; i++) {
    if (as[i] && !classTest(as[i]).test(b)) {
      b += ' ' + as[i]
    }
  }
  return b
}

var selectInput = function (node) {
  node.select()
}
if (ios) // Mobile Safari apparently has a bug where select() is broken.
{
  selectInput = function (node) {
    node.selectionStart = 0
    node.selectionEnd = node.value.length
  }
} else if (ie) // Suppress mysterious IE10 errors
{
  selectInput = function (node) {
    try {
      node.select()
    } catch (_e) {
    }
  }
}

function bind (f) {
  var args = Array.prototype.slice.call(arguments, 1)
  return function () {
    return f.apply(null, args)
  }
}

function copyObj (obj, target, overwrite) {
  if (!target) {
    target = {}
  }
  for (var prop in obj) {
    if (obj.hasOwnProperty(prop) && (overwrite !== false || !target.hasOwnProperty(prop))) {
      target[prop] = obj[prop]
    }
  }
  return target
}

// Counts the column offset in a string, taking tabs into account.
// Used mostly to find indentation.
function countColumn (string, end, tabSize, startIndex, startValue) {
  if (end == null) {
    end = string.search(/[^\s\u00a0]/)
    if (end == -1) {
      end = string.length
    }
  }
  for (var i = startIndex || 0, n = startValue || 0; ;) {
    var nextTab = string.indexOf('\t', i)
    if (nextTab < 0 || nextTab >= end) {
      return n + (end - i)
    }
    n += nextTab - i
    n += tabSize - (n % tabSize)
    i = nextTab + 1
  }
}

var Delayed = function () {
  this.id = null
  this.f = null
  this.time = 0
  this.handler = bind(this.onTimeout, this)
}
Delayed.prototype.onTimeout = function (self) {
  self.id = 0
  if (self.time <= +new Date()) {
    self.f()
  } else {
    setTimeout(self.handler, self.time - +new Date())
  }
}
Delayed.prototype.set = function (ms, f) {
  this.f = f
  var time = +new Date() + ms
  if (!this.id || time < this.time) {
    clearTimeout(this.id)
    this.id = setTimeout(this.handler, ms)
    this.time = time
  }
}

function indexOf (array, elt) {
  for (var i = 0; i < array.length; ++i) {
    if (array[i] == elt) {
      return i
    }
  }
  return -1
}

// Number of pixels added to scroller and sizer to hide scrollbar
var scrollerGap = 30

// Returned or thrown by various protocols to signal 'I'm not
// handling this'.
var Pass = {
  toString: function () {
    return 'CodeMirror.Pass'
  }
}

// Reused option objects for setSelection & friends
var sel_dontScroll = { scroll: false }; var sel_mouse = { origin: '*mouse' }; var sel_move = { origin: '+move' }

// The inverse of countColumn -- find the offset that corresponds to
// a particular column.
function findColumn (string, goal, tabSize) {
  for (var pos = 0, col = 0; ;) {
    var nextTab = string.indexOf('\t', pos)
    if (nextTab == -1) {
      nextTab = string.length
    }
    var skipped = nextTab - pos
    if (nextTab == string.length || col + skipped >= goal) {
      return pos + Math.min(skipped, goal - col)
    }
    col += nextTab - pos
    col += tabSize - (col % tabSize)
    pos = nextTab + 1
    if (col >= goal) {
      return pos
    }
  }
}

var spaceStrs = ['']

function spaceStr (n) {
  while (spaceStrs.length <= n) {
    spaceStrs.push(lst(spaceStrs) + ' ')
  }
  return spaceStrs[n]
}

function lst (arr) {
  return arr[arr.length - 1]
}

function map (array, f) {
  var out = []
  for (var i = 0; i < array.length; i++) {
    out[i] = f(array[i], i)
  }
  return out
}

function insertSorted (array, value, score) {
  var pos = 0; var priority = score(value)
  while (pos < array.length && score(array[pos]) <= priority) {
    pos++
  }
  array.splice(pos, 0, value)
}

function nothing () {
}

function createObj (base, props) {
  var inst
  if (Object.create) {
    inst = Object.create(base)
  } else {
    nothing.prototype = base
    inst = new nothing()
  }
  if (props) {
    copyObj(props, inst)
  }
  return inst
}

var nonASCIISingleCaseWordChar = /[\u00df\u0587\u0590-\u05f4\u0600-\u06ff\u3040-\u309f\u30a0-\u30ff\u3400-\u4db5\u4e00-\u9fcc\uac00-\ud7af]/

function isWordCharBasic (ch) {
  return /\w/.test(ch) || ch > '\x80' &&
        (ch.toUpperCase() != ch.toLowerCase() || nonASCIISingleCaseWordChar.test(ch))
}

function isWordChar (ch, helper) {
  if (!helper) {
    return isWordCharBasic(ch)
  }
  if (helper.source.indexOf('\\w') > -1 && isWordCharBasic(ch)) {
    return true
  }
  return helper.test(ch)
}

function isEmpty (obj) {
  for (var n in obj) {
    if (obj.hasOwnProperty(n) && obj[n]) {
      return false
    }
  }
  return true
}

// Extending unicode characters. A series of a non-extending char +
// any number of extending chars is treated as a single unit as far
// as editing and measuring is concerned. This is not fully correct,
// since some scripts/fonts/browsers also treat other configurations
// of code points as a group.
var extendingChars = /[\u0300-\u036f\u0483-\u0489\u0591-\u05bd\u05bf\u05c1\u05c2\u05c4\u05c5\u05c7\u0610-\u061a\u064b-\u065e\u0670\u06d6-\u06dc\u06de-\u06e4\u06e7\u06e8\u06ea-\u06ed\u0711\u0730-\u074a\u07a6-\u07b0\u07eb-\u07f3\u0816-\u0819\u081b-\u0823\u0825-\u0827\u0829-\u082d\u0900-\u0902\u093c\u0941-\u0948\u094d\u0951-\u0955\u0962\u0963\u0981\u09bc\u09be\u09c1-\u09c4\u09cd\u09d7\u09e2\u09e3\u0a01\u0a02\u0a3c\u0a41\u0a42\u0a47\u0a48\u0a4b-\u0a4d\u0a51\u0a70\u0a71\u0a75\u0a81\u0a82\u0abc\u0ac1-\u0ac5\u0ac7\u0ac8\u0acd\u0ae2\u0ae3\u0b01\u0b3c\u0b3e\u0b3f\u0b41-\u0b44\u0b4d\u0b56\u0b57\u0b62\u0b63\u0b82\u0bbe\u0bc0\u0bcd\u0bd7\u0c3e-\u0c40\u0c46-\u0c48\u0c4a-\u0c4d\u0c55\u0c56\u0c62\u0c63\u0cbc\u0cbf\u0cc2\u0cc6\u0ccc\u0ccd\u0cd5\u0cd6\u0ce2\u0ce3\u0d3e\u0d41-\u0d44\u0d4d\u0d57\u0d62\u0d63\u0dca\u0dcf\u0dd2-\u0dd4\u0dd6\u0ddf\u0e31\u0e34-\u0e3a\u0e47-\u0e4e\u0eb1\u0eb4-\u0eb9\u0ebb\u0ebc\u0ec8-\u0ecd\u0f18\u0f19\u0f35\u0f37\u0f39\u0f71-\u0f7e\u0f80-\u0f84\u0f86\u0f87\u0f90-\u0f97\u0f99-\u0fbc\u0fc6\u102d-\u1030\u1032-\u1037\u1039\u103a\u103d\u103e\u1058\u1059\u105e-\u1060\u1071-\u1074\u1082\u1085\u1086\u108d\u109d\u135f\u1712-\u1714\u1732-\u1734\u1752\u1753\u1772\u1773\u17b7-\u17bd\u17c6\u17c9-\u17d3\u17dd\u180b-\u180d\u18a9\u1920-\u1922\u1927\u1928\u1932\u1939-\u193b\u1a17\u1a18\u1a56\u1a58-\u1a5e\u1a60\u1a62\u1a65-\u1a6c\u1a73-\u1a7c\u1a7f\u1b00-\u1b03\u1b34\u1b36-\u1b3a\u1b3c\u1b42\u1b6b-\u1b73\u1b80\u1b81\u1ba2-\u1ba5\u1ba8\u1ba9\u1c2c-\u1c33\u1c36\u1c37\u1cd0-\u1cd2\u1cd4-\u1ce0\u1ce2-\u1ce8\u1ced\u1dc0-\u1de6\u1dfd-\u1dff\u200c\u200d\u20d0-\u20f0\u2cef-\u2cf1\u2de0-\u2dff\u302a-\u302f\u3099\u309a\ua66f-\ua672\ua67c\ua67d\ua6f0\ua6f1\ua802\ua806\ua80b\ua825\ua826\ua8c4\ua8e0-\ua8f1\ua926-\ua92d\ua947-\ua951\ua980-\ua982\ua9b3\ua9b6-\ua9b9\ua9bc\uaa29-\uaa2e\uaa31\uaa32\uaa35\uaa36\uaa43\uaa4c\uaab0\uaab2-\uaab4\uaab7\uaab8\uaabe\uaabf\uaac1\uabe5\uabe8\uabed\udc00-\udfff\ufb1e\ufe00-\ufe0f\ufe20-\ufe26\uff9e\uff9f]/

function isExtendingChar (ch) {
  return ch.charCodeAt(0) >= 768 && extendingChars.test(ch)
}

// Returns a number from the range [`0`; `str.length`] unless `pos` is outside that range.
function skipExtendingChars (str, pos, dir) {
  while ((dir < 0 ? pos > 0 : pos < str.length) && isExtendingChar(str.charAt(pos))) {
    pos += dir
  }
  return pos
}

// Returns the value from the range [`from`; `to`] that satisfies
// `pred` and is closest to `from`. Assumes that at least `to`
// satisfies `pred`. Supports `from` being greater than `to`.
function findFirst (pred, from, to) {
  // At any point we are certain `to` satisfies `pred`, don't know
  // whether `from` does.
  var dir = from > to ? -1 : 1
  for (; ;) {
    if (from == to) {
      return from
    }
    var midF = (from + to) / 2; var mid = dir < 0 ? Math.ceil(midF) : Math.floor(midF)
    if (mid == from) {
      return pred(mid) ? from : to
    }
    if (pred(mid)) {
      to = mid
    } else {
      from = mid + dir
    }
  }
}

// BIDI HELPERS

function iterateBidiSections (order, from, to, f) {
  if (!order) {
    return f(from, to, 'ltr', 0)
  }
  var found = false
  for (var i = 0; i < order.length; ++i) {
    var part = order[i]
    if (part.from < to && part.to > from || from == to && part.to == from) {
      f(Math.max(part.from, from), Math.min(part.to, to), part.level == 1 ? 'rtl' : 'ltr', i)
      found = true
    }
  }
  if (!found) {
    f(from, to, 'ltr')
  }
}

var bidiOther = null

function getBidiPartAt (order, ch, sticky) {
  var found
  bidiOther = null
  for (var i = 0; i < order.length; ++i) {
    var cur = order[i]
    if (cur.from < ch && cur.to > ch) {
      return i
    }
    if (cur.to == ch) {
      if (cur.from != cur.to && sticky == 'before') {
        found = i
      } else {
        bidiOther = i
      }
    }
    if (cur.from == ch) {
      if (cur.from != cur.to && sticky != 'before') {
        found = i
      } else {
        bidiOther = i
      }
    }
  }
  return found != null ? found : bidiOther
}

// Bidirectional ordering algorithm
// See http://unicode.org/reports/tr9/tr9-13.html for the algorithm
// that this (partially) implements.

// One-char codes used for character types:
// L (L):   Left-to-Right
// R (R):   Right-to-Left
// r (AL):  Right-to-Left Arabic
// 1 (EN):  European Number
// + (ES):  European Number Separator
// % (ET):  European Number Terminator
// n (AN):  Arabic Number
// , (CS):  Common Number Separator
// m (NSM): Non-Spacing Mark
// b (BN):  Boundary Neutral
// s (B):   Paragraph Separator
// t (S):   Segment Separator
// w (WS):  Whitespace
// N (ON):  Other Neutrals

// Returns null if characters are ordered as they appear
// (left-to-right), or an array of sections ({from, to, level}
// objects) in the order in which they occur visually.
var bidiOrdering = (function () {
  // Character types for codepoints 0 to 0xff
  var lowTypes = 'bbbbbbbbbtstwsbbbbbbbbbbbbbbssstwNN%%%NNNNNN,N,N1111111111NNNNNNNLLLLLLLLLLLLLLLLLLLLLLLLLLNNNNNNLLLLLLLLLLLLLLLLLLLLLLLLLLNNNNbbbbbbsbbbbbbbbbbbbbbbbbbbbbbbbbb,N%%%%NNNNLNNNNN%%11NLNNN1LNNNNNLLLLLLLLLLLLLLLLLLLLLLLNLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLN'
  // Character types for codepoints 0x600 to 0x6f9
  var arabicTypes = 'nnnnnnNNr%%r,rNNmmmmmmmmmmmrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrmmmmmmmmmmmmmmmmmmmmmnnnnnnnnnn%nnrrrmrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrmmmmmmmnNmmmmmmrrmmNmmmmrr1111111111'

  function charType (code) {
    if (code <= 0xf7) {
      return lowTypes.charAt(code)
    } else if (code >= 0x590 && code <= 0x5f4) {
      return 'R'
    } else if (code >= 0x600 && code <= 0x6f9) {
      return arabicTypes.charAt(code - 0x600)
    } else if (code >= 0x6ee && code <= 0x8ac) {
      return 'r'
    } else if (code >= 0x2000 && code <= 0x200b) {
      return 'w'
    } else if (code == 0x200c) {
      return 'b'
    } else {
      return 'L'
    }
  }

  var bidiRE = /[\u0590-\u05f4\u0600-\u06ff\u0700-\u08ac]/
  var isNeutral = /[stwN]/; var isStrong = /[LRr]/; var countsAsLeft = /[Lb1n]/; var countsAsNum = /[1n]/

  function BidiSpan (level, from, to) {
    this.level = level
    this.from = from
    this.to = to
  }

  return function (str, direction) {
    var outerType = direction == 'ltr' ? 'L' : 'R'

    if (str.length == 0 || direction == 'ltr' && !bidiRE.test(str)) {
      return false
    }
    var len = str.length; var types = []
    for (var i = 0; i < len; ++i) {
      types.push(charType(str.charCodeAt(i)))
    }

    // W1. Examine each non-spacing mark (NSM) in the level run, and
    // change the type of the NSM to the type of the previous
    // character. If the NSM is at the start of the level run, it will
    // get the type of sor.
    for (var i$1 = 0, prev = outerType; i$1 < len; ++i$1) {
      var type = types[i$1]
      if (type == 'm') {
        types[i$1] = prev
      } else {
        prev = type
      }
    }

    // W2. Search backwards from each instance of a European number
    // until the first strong type (R, L, AL, or sor) is found. If an
    // AL is found, change the type of the European number to Arabic
    // number.
    // W3. Change all ALs to R.
    for (var i$2 = 0, cur = outerType; i$2 < len; ++i$2) {
      var type$1 = types[i$2]
      if (type$1 == '1' && cur == 'r') {
        types[i$2] = 'n'
      } else if (isStrong.test(type$1)) {
        cur = type$1
        if (type$1 == 'r') {
          types[i$2] = 'R'
        }
      }
    }

    // W4. A single European separator between two European numbers
    // changes to a European number. A single common separator between
    // two numbers of the same type changes to that type.
    for (var i$3 = 1, prev$1 = types[0]; i$3 < len - 1; ++i$3) {
      var type$2 = types[i$3]
      if (type$2 == '+' && prev$1 == '1' && types[i$3 + 1] == '1') {
        types[i$3] = '1'
      } else if (type$2 == ',' && prev$1 == types[i$3 + 1] &&
                (prev$1 == '1' || prev$1 == 'n')) {
        types[i$3] = prev$1
      }
      prev$1 = type$2
    }

    // W5. A sequence of European terminators adjacent to European
    // numbers changes to all European numbers.
    // W6. Otherwise, separators and terminators change to Other
    // Neutral.
    for (var i$4 = 0; i$4 < len; ++i$4) {
      var type$3 = types[i$4]
      if (type$3 == ',') {
        types[i$4] = 'N'
      } else if (type$3 == '%') {
        var end = (void 0)
        for (end = i$4 + 1; end < len && types[end] == '%'; ++end) {
        }
        var replace = (i$4 && types[i$4 - 1] == '!') || (end < len && types[end] == '1') ? '1' : 'N'
        for (var j = i$4; j < end; ++j) {
          types[j] = replace
        }
        i$4 = end - 1
      }
    }

    // W7. Search backwards from each instance of a European number
    // until the first strong type (R, L, or sor) is found. If an L is
    // found, then change the type of the European number to L.
    for (var i$5 = 0, cur$1 = outerType; i$5 < len; ++i$5) {
      var type$4 = types[i$5]
      if (cur$1 == 'L' && type$4 == '1') {
        types[i$5] = 'L'
      } else if (isStrong.test(type$4)) {
        cur$1 = type$4
      }
    }

    // N1. A sequence of neutrals takes the direction of the
    // surrounding strong text if the text on both sides has the same
    // direction. European and Arabic numbers act as if they were R in
    // terms of their influence on neutrals. Start-of-level-run (sor)
    // and end-of-level-run (eor) are used at level run boundaries.
    // N2. Any remaining neutrals take the embedding direction.
    for (var i$6 = 0; i$6 < len; ++i$6) {
      if (isNeutral.test(types[i$6])) {
        var end$1 = (void 0)
        for (end$1 = i$6 + 1; end$1 < len && isNeutral.test(types[end$1]); ++end$1) {
        }
        var before = (i$6 ? types[i$6 - 1] : outerType) == 'L'
        var after = (end$1 < len ? types[end$1] : outerType) == 'L'
        var replace$1 = before == after ? (before ? 'L' : 'R') : outerType
        for (var j$1 = i$6; j$1 < end$1; ++j$1) {
          types[j$1] = replace$1
        }
        i$6 = end$1 - 1
      }
    }

    // Here we depart from the documented algorithm, in order to avoid
    // building up an actual levels array. Since there are only three
    // levels (0, 1, 2) in an implementation that doesn't take
    // explicit embedding into account, we can build up the order on
    // the fly, without following the level-based algorithm.
    var order = []; var m
    for (var i$7 = 0; i$7 < len;) {
      if (countsAsLeft.test(types[i$7])) {
        var start = i$7
        for (++i$7; i$7 < len && countsAsLeft.test(types[i$7]); ++i$7) {
        }
        order.push(new BidiSpan(0, start, i$7))
      } else {
        var pos = i$7; var at = order.length
        for (++i$7; i$7 < len && types[i$7] != 'L'; ++i$7) {
        }
        for (var j$2 = pos; j$2 < i$7;) {
          if (countsAsNum.test(types[j$2])) {
            if (pos < j$2) {
              order.splice(at, 0, new BidiSpan(1, pos, j$2))
            }
            var nstart = j$2
            for (++j$2; j$2 < i$7 && countsAsNum.test(types[j$2]); ++j$2) {
            }
            order.splice(at, 0, new BidiSpan(2, nstart, j$2))
            pos = j$2
          } else {
            ++j$2
          }
        }
        if (pos < i$7) {
          order.splice(at, 0, new BidiSpan(1, pos, i$7))
        }
      }
    }
    if (direction == 'ltr') {
      if (order[0].level == 1 && (m = str.match(/^\s+/))) {
        order[0].from = m[0].length
        order.unshift(new BidiSpan(0, 0, m[0].length))
      }
      if (lst(order).level == 1 && (m = str.match(/\s+$/))) {
        lst(order).to -= m[0].length
        order.push(new BidiSpan(0, len - m[0].length, len))
      }
    }

    return direction == 'rtl' ? order.reverse() : order
  }
})()

// Get the bidi ordering for the given line (and cache it). Returns
// false for lines that are fully left-to-right, and an array of
// BidiSpan objects otherwise.
function getOrder (line, direction) {
  var order = line.order
  if (order == null) {
    order = line.order = bidiOrdering(line.text, direction)
  }
  return order
}
var noHandlers = []

var on = function (emitter, type, f) {
  if (emitter.addEventListener) {
    emitter.addEventListener(type, f, false)
  } else if (emitter.attachEvent) {
    emitter.attachEvent('on' + type, f)
  } else {
    var map$$1 = emitter._handlers || (emitter._handlers = {})
    map$$1[type] = (map$$1[type] || noHandlers).concat(f)
  }
}

function getHandlers (emitter, type) {
  return emitter._handlers && emitter._handlers[type] || noHandlers
}
function off (emitter, type, f) {
  if (emitter.removeEventListener) {
    emitter.removeEventListener(type, f, false)
  } else if (emitter.detachEvent) {
    emitter.detachEvent('on' + type, f)
  } else {
    var map$$1 = emitter._handlers; var arr = map$$1 && map$$1[type]
    if (arr) {
      var index = indexOf(arr, f)
      if (index > -1) {
        map$$1[type] = arr.slice(0, index).concat(arr.slice(index + 1))
      }
    }
  }
}

function signal (emitter, type /*, values... */) {
  var handlers = getHandlers(emitter, type)
  if (!handlers.length) {
    return
  }
  var args = Array.prototype.slice.call(arguments, 2)
  for (var i = 0; i < handlers.length; ++i) {
    handlers[i].apply(null, args)
  }
}

// The DOM events that CodeMirror handles can be overridden by
// registering a (non-DOM) handler on the src for the event name,
// and preventDefault-ing the event in that handler.
function signalDOMEvent (cm, e, override) {
  if (typeof e === 'string') {
    e = {
      type: e,
      preventDefault: function () {
        this.defaultPrevented = true
      }
    }
  }
  signal(cm, override || e.type, cm, e)
  return e_defaultPrevented(e) || e.codemirrorIgnore
}

function signalCursorActivity (cm) {
  var arr = cm._handlers && cm._handlers.cursorActivity
  if (!arr) {
    return
  }
  var set = cm.curOp.cursorActivityHandlers || (cm.curOp.cursorActivityHandlers = [])
  for (var i = 0; i < arr.length; ++i) {
    if (indexOf(set, arr[i]) == -1) {
      set.push(arr[i])
    }
  }
}

function hasHandler (emitter, type) {
  return getHandlers(emitter, type).length > 0
}

// Add on and off methods to a constructor's prototype, to make
// registering events on such objects more convenient.
function eventMixin (ctor) {
  ctor.prototype.on = function (type, f) {
    on(this, type, f)
  }
  ctor.prototype.off = function (type, f) {
    off(this, type, f)
  }
}

// Due to the fact that we still support jurassic IE versions, some
// compatibility wrappers are needed.

function e_preventDefault (e) {
  if (e.preventDefault) {
    e.preventDefault()
  } else {
    e.returnValue = false
  }
}

function e_stopPropagation (e) {
  if (e.stopPropagation) {
    e.stopPropagation()
  } else {
    e.cancelBubble = true
  }
}

function e_defaultPrevented (e) {
  return e.defaultPrevented != null ? e.defaultPrevented : e.returnValue == false
}

function e_stop (e) {
  e_preventDefault(e)
  e_stopPropagation(e)
}

function e_target (e) {
  return e.target || e.srcElement
}

function e_button (e) {
  var b = e.which
  if (b == null) {
    if (e.button & 1) {
      b = 1
    } else if (e.button & 2) {
      b = 3
    } else if (e.button & 4) {
      b = 2
    }
  }
  if (mac && e.ctrlKey && b == 1) {
    b = 3
  }
  return b
}

// Detect drag-and-drop
var dragAndDrop = (function () {
  // There is *some* kind of drag-and-drop support in IE6-8, but I
  // couldn't get it to work yet.
  if (ie && ie_version < 9) {
    return false
  }
  var div = elt('div')
  return 'draggable' in div || 'dragDrop' in div
}())

var zwspSupported

function zeroWidthElement (measure) {
  if (zwspSupported == null) {
    var test = elt('span', '\u200b')
    removeChildrenAndAdd(measure, elt('span', [test, document.createTextNode('x')]))
    if (measure.firstChild.offsetHeight != 0) {
      zwspSupported = test.offsetWidth <= 1 && test.offsetHeight > 2 && !(ie && ie_version < 8)
    }
  }
  var node = zwspSupported ? elt('span', '\u200b')
    : elt('span', '\u00a0', null, 'display: inline-block; width: 1px; margin-right: -1px')
  node.setAttribute('cm-text', '')
  return node
}

// Feature-detect IE's crummy client rect reporting for bidi text
var badBidiRects

function hasBadBidiRects (measure) {
  if (badBidiRects != null) {
    return badBidiRects
  }
  var txt = removeChildrenAndAdd(measure, document.createTextNode('A\u062eA'))
  var r0 = range(txt, 0, 1).getBoundingClientRect()
  var r1 = range(txt, 1, 2).getBoundingClientRect()
  removeChildren(measure)
  if (!r0 || r0.left == r0.right) {
    return false
  } // Safari returns null in some cases (#2780)
  return badBidiRects = (r1.right - r0.right < 3)
}

// See if "".split is the broken IE version, if so, provide an
// alternative way to split lines.
var splitLinesAuto = '\n\nb'.split(/\n/).length != 3 ? function (string) {
  var pos = 0; var result = []; var l = string.length
  while (pos <= l) {
    var nl = string.indexOf('\n', pos)
    if (nl == -1) {
      nl = string.length
    }
    var line = string.slice(pos, string.charAt(nl - 1) == '\r' ? nl - 1 : nl)
    var rt = line.indexOf('\r')
    if (rt != -1) {
      result.push(line.slice(0, rt))
      pos += rt + 1
    } else {
      result.push(line)
      pos = nl + 1
    }
  }
  return result
} : function (string) {
  return string.split(/\r\n?|\n/)
}

var hasSelection = window.getSelection ? function (te) {
  try {
    return te.selectionStart != te.selectionEnd
  } catch (e) {
    return false
  }
} : function (te) {
  var range$$1
  try {
    range$$1 = te.ownerDocument.selection.createRange()
  } catch (e) {
  }
  if (!range$$1 || range$$1.parentElement() != te) {
    return false
  }
  return range$$1.compareEndPoints('StartToEnd', range$$1) != 0
}

var hasCopyEvent = (function () {
  var e = elt('div')
  if ('oncopy' in e) {
    return true
  }
  e.setAttribute('oncopy', 'return;')
  return typeof e.oncopy === 'function'
})()

var badZoomedRects = null

function hasBadZoomedRects (measure) {
  if (badZoomedRects != null) {
    return badZoomedRects
  }
  var node = removeChildrenAndAdd(measure, elt('span', 'x'))
  var normal = node.getBoundingClientRect()
  var fromRange = range(node, 0, 1).getBoundingClientRect()
  return badZoomedRects = Math.abs(normal.left - fromRange.left) > 1
}

// Known modes, by name and by MIME
var modes = {}; var mimeModes = {}

// Extra arguments are stored as the mode's dependencies, which is
// used by (legacy) mechanisms like loadmode.js to automatically
// load a mode. (Preferred mechanism is the require/define calls.)
function defineMode (name, mode) {
  if (arguments.length > 2) {
    mode.dependencies = Array.prototype.slice.call(arguments, 2)
  }
  modes[name] = mode
}

function defineMIME (mime, spec) {
  mimeModes[mime] = spec
}

// Given a MIME type, a {name, ...options} config object, or a name
// string, return a mode config object.
function resolveMode (spec) {
  if (typeof spec === 'string' && mimeModes.hasOwnProperty(spec)) {
    spec = mimeModes[spec]
  } else if (spec && typeof spec.name === 'string' && mimeModes.hasOwnProperty(spec.name)) {
    var found = mimeModes[spec.name]
    if (typeof found === 'string') {
      found = { name: found }
    }
    spec = createObj(found, spec)
    spec.name = found.name
  } else if (typeof spec === 'string' && /^[\w\-]+\/[\w\-]+\+xml$/.test(spec)) {
    return resolveMode('application/xml')
  } else if (typeof spec === 'string' && /^[\w\-]+\/[\w\-]+\+json$/.test(spec)) {
    return resolveMode('application/json')
  }
  if (typeof spec === 'string') {
    return { name: spec }
  } else {
    return spec || { name: 'null' }
  }
}

// Given a mode spec (anything that resolveMode accepts), find and
// initialize an actual mode object.
function getMode (options, spec) {
  spec = resolveMode(spec)
  var mfactory = modes[spec.name]
  if (!mfactory) {
    return getMode(options, 'text/plain')
  }
  var modeObj = mfactory(options, spec)
  if (modeExtensions.hasOwnProperty(spec.name)) {
    var exts = modeExtensions[spec.name]
    for (var prop in exts) {
      if (!exts.hasOwnProperty(prop)) {
        continue
      }
      if (modeObj.hasOwnProperty(prop)) {
        modeObj['_' + prop] = modeObj[prop]
      }
      modeObj[prop] = exts[prop]
    }
  }
  modeObj.name = spec.name
  if (spec.helperType) {
    modeObj.helperType = spec.helperType
  }
  if (spec.modeProps) {
    for (var prop$1 in spec.modeProps) {
      modeObj[prop$1] = spec.modeProps[prop$1]
    }
  }

  return modeObj
}

// This can be used to attach properties to mode objects from
// outside the actual mode definition.
var modeExtensions = {}

function extendMode (mode, properties) {
  var exts = modeExtensions.hasOwnProperty(mode) ? modeExtensions[mode] : (modeExtensions[mode] = {})
  copyObj(properties, exts)
}

function copyState (mode, state) {
  if (state === true) {
    return state
  }
  if (mode.copyState) {
    return mode.copyState(state)
  }
  var nstate = {}
  for (var n in state) {
    var val = state[n]
    if (val instanceof Array) {
      val = val.concat([])
    }
    nstate[n] = val
  }
  return nstate
}

// Given a mode and a state (for that mode), find the inner mode and
// state at the position that the state refers to.
function innerMode (mode, state) {
  var info
  while (mode.innerMode) {
    info = mode.innerMode(state)
    if (!info || info.mode == mode) {
      break
    }
    state = info.state
    mode = info.mode
  }
  return info || { mode: mode, state: state }
}

function startState (mode, a1, a2) {
  return mode.startState ? mode.startState(a1, a2) : true
}

// STRING STREAM

// Fed to the mode parsers, provides helper functions to make
// parsers more succinct.

var StringStream = function (string, tabSize, lineOracle) {
  this.pos = this.start = 0
  this.string = string
  this.tabSize = tabSize || 8
  this.lastColumnPos = this.lastColumnValue = 0
  this.lineStart = 0
  this.lineOracle = lineOracle
}

StringStream.prototype.eol = function () {
  return this.pos >= this.string.length
}
StringStream.prototype.sol = function () {
  return this.pos == this.lineStart
}
StringStream.prototype.peek = function () {
  return this.string.charAt(this.pos) || undefined
}
StringStream.prototype.next = function () {
  if (this.pos < this.string.length) {
    return this.string.charAt(this.pos++)
  }
}
StringStream.prototype.eat = function (match) {
  var ch = this.string.charAt(this.pos)
  var ok
  if (typeof match === 'string') {
    ok = ch == match
  } else {
    ok = ch && (match.test ? match.test(ch) : match(ch))
  }
  if (ok) {
    ++this.pos
    return ch
  }
}
StringStream.prototype.eatWhile = function (match) {
  var start = this.pos
  while (this.eat(match)) {
  }
  return this.pos > start
}
StringStream.prototype.eatSpace = function () {
  var this$1 = this

  var start = this.pos
  while (/[\s\u00a0]/.test(this.string.charAt(this.pos))) {
    ++this$1.pos
  }
  return this.pos > start
}
StringStream.prototype.skipToEnd = function () {
  this.pos = this.string.length
}
StringStream.prototype.skipTo = function (ch) {
  var found = this.string.indexOf(ch, this.pos)
  if (found > -1) {
    this.pos = found
    return true
  }
}
StringStream.prototype.backUp = function (n) {
  this.pos -= n
}
StringStream.prototype.column = function () {
  if (this.lastColumnPos < this.start) {
    this.lastColumnValue = countColumn(this.string, this.start, this.tabSize, this.lastColumnPos, this.lastColumnValue)
    this.lastColumnPos = this.start
  }
  return this.lastColumnValue - (this.lineStart ? countColumn(this.string, this.lineStart, this.tabSize) : 0)
}
StringStream.prototype.indentation = function () {
  return countColumn(this.string, null, this.tabSize) -
        (this.lineStart ? countColumn(this.string, this.lineStart, this.tabSize) : 0)
}
StringStream.prototype.match = function (pattern, consume, caseInsensitive) {
  if (typeof pattern === 'string') {
    var cased = function (str) {
      return caseInsensitive ? str.toLowerCase() : str
    }
    var substr = this.string.substr(this.pos, pattern.length)
    if (cased(substr) == cased(pattern)) {
      if (consume !== false) {
        this.pos += pattern.length
      }
      return true
    }
  } else {
    var match = this.string.slice(this.pos).match(pattern)
    if (match && match.index > 0) {
      return null
    }
    if (match && consume !== false) {
      this.pos += match[0].length
    }
    return match
  }
}
StringStream.prototype.current = function () {
  return this.string.slice(this.start, this.pos)
}
StringStream.prototype.hideFirstChars = function (n, inner) {
  this.lineStart += n
  try {
    return inner()
  } finally {
    this.lineStart -= n
  }
}
StringStream.prototype.lookAhead = function (n) {
  var oracle = this.lineOracle
  return oracle && oracle.lookAhead(n)
}
StringStream.prototype.baseToken = function () {
  var oracle = this.lineOracle
  return oracle && oracle.baseToken(this.pos)
}

// Find the line object corresponding to the given line number.
function getLine (doc, n) {
  n -= doc.first
  if (n < 0 || n >= doc.size) {
    throw new Error('There is no line ' + (n + doc.first) + ' in the document.')
  }
  var chunk = doc
  while (!chunk.lines) {
    for (var i = 0; ; ++i) {
      var child = chunk.children[i]; var sz = child.chunkSize()
      if (n < sz) {
        chunk = child
        break
      }
      n -= sz
    }
  }
  return chunk.lines[n]
}

// Get the part of a document between two positions, as an array of
// strings.
function getBetween (doc, start, end) {
  var out = []; var n = start.line
  doc.iter(start.line, end.line + 1, function (line) {
    var text = line.text
    if (n == end.line) {
      text = text.slice(0, end.ch)
    }
    if (n == start.line) {
      text = text.slice(start.ch)
    }
    out.push(text)
    ++n
  })
  return out
}

// Get the lines between from and to, as array of strings.
function getLines (doc, from, to) {
  var out = []
  doc.iter(from, to, function (line) {
    out.push(line.text)
  }) // iter aborts when callback returns truthy value
  return out
}

// Update the height of a line, propagating the height change
// upwards to parent nodes.
function updateLineHeight (line, height) {
  var diff = height - line.height
  if (diff) {
    for (var n = line; n; n = n.parent) {
      n.height += diff
    }
  }
}

// Given a line object, find its line number by walking up through
// its parent links.
function lineNo (line) {
  if (line.parent == null) {
    return null
  }
  var cur = line.parent; var no = indexOf(cur.lines, line)
  for (var chunk = cur.parent; chunk; cur = chunk, chunk = chunk.parent) {
    for (var i = 0; ; ++i) {
      if (chunk.children[i] == cur) {
        break
      }
      no += chunk.children[i].chunkSize()
    }
  }
  return no + cur.first
}

// Find the line at the given vertical position, using the height
// information in the document tree.
function lineAtHeight (chunk, h) {
  var n = chunk.first
  outer: do {
    for (var i$1 = 0; i$1 < chunk.children.length; ++i$1) {
      var child = chunk.children[i$1]; var ch = child.height
      if (h < ch) {
        chunk = child
        continue outer
      }
      h -= ch
      n += child.chunkSize()
    }
    return n
  } while (!chunk.lines)
  var i = 0
  for (; i < chunk.lines.length; ++i) {
    var line = chunk.lines[i]; var lh = line.height
    if (h < lh) {
      break
    }
    h -= lh
  }
  return n + i
}

function isLine (doc, l) {
  return l >= doc.first && l < doc.first + doc.size
}

function lineNumberFor (options, i) {
  return String(options.lineNumberFormatter(i + options.firstLineNumber))
}

// A Pos instance represents a position within the text.
function Pos (line, ch, sticky) {
  if (sticky === void 0) sticky = null

  if (!(this instanceof Pos)) {
    return new Pos(line, ch, sticky)
  }
  this.line = line
  this.ch = ch
  this.sticky = sticky
}

// Compare two positions, return 0 if they are the same, a negative
// number when a is less, and a positive number otherwise.
function cmp (a, b) {
  return a.line - b.line || a.ch - b.ch
}

function equalCursorPos (a, b) {
  return a.sticky == b.sticky && cmp(a, b) == 0
}

function copyPos (x) {
  return Pos(x.line, x.ch)
}

function maxPos (a, b) {
  return cmp(a, b) < 0 ? b : a
}

function minPos (a, b) {
  return cmp(a, b) < 0 ? a : b
}

// Most of the external API clips given positions to make sure they
// actually exist within the document.
function clipLine (doc, n) {
  return Math.max(doc.first, Math.min(n, doc.first + doc.size - 1))
}

function clipPos (doc, pos) {
  if (pos.line < doc.first) {
    return Pos(doc.first, 0)
  }
  var last = doc.first + doc.size - 1
  if (pos.line > last) {
    return Pos(last, getLine(doc, last).text.length)
  }
  return clipToLen(pos, getLine(doc, pos.line).text.length)
}

function clipToLen (pos, linelen) {
  var ch = pos.ch
  if (ch == null || ch > linelen) {
    return Pos(pos.line, linelen)
  } else if (ch < 0) {
    return Pos(pos.line, 0)
  } else {
    return pos
  }
}

function clipPosArray (doc, array) {
  var out = []
  for (var i = 0; i < array.length; i++) {
    out[i] = clipPos(doc, array[i])
  }
  return out
}

var SavedContext = function (state, lookAhead) {
  this.state = state
  this.lookAhead = lookAhead
}

var Context = function (doc, state, line, lookAhead) {
  this.state = state
  this.doc = doc
  this.line = line
  this.maxLookAhead = lookAhead || 0
  this.baseTokens = null
  this.baseTokenPos = 1
}

Context.prototype.lookAhead = function (n) {
  var line = this.doc.getLine(this.line + n)
  if (line != null && n > this.maxLookAhead) {
    this.maxLookAhead = n
  }
  return line
}

Context.prototype.baseToken = function (n) {
  var this$1 = this

  if (!this.baseTokens) {
    return null
  }
  while (this.baseTokens[this.baseTokenPos] <= n) {
    this$1.baseTokenPos += 2
  }
  var type = this.baseTokens[this.baseTokenPos + 1]
  return {
    type: type && type.replace(/( |^)overlay .*/, ''),
    size: this.baseTokens[this.baseTokenPos] - n
  }
}

Context.prototype.nextLine = function () {
  this.line++
  if (this.maxLookAhead > 0) {
    this.maxLookAhead--
  }
}

Context.fromSaved = function (doc, saved, line) {
  if (saved instanceof SavedContext) {
    return new Context(doc, copyState(doc.mode, saved.state), line, saved.lookAhead)
  } else {
    return new Context(doc, copyState(doc.mode, saved), line)
  }
}

Context.prototype.save = function (copy) {
  var state = copy !== false ? copyState(this.doc.mode, this.state) : this.state
  return this.maxLookAhead > 0 ? new SavedContext(state, this.maxLookAhead) : state
}

// Compute a style array (an array starting with a mode generation
// -- for invalidation -- followed by pairs of end positions and
// style strings), which is used to highlight the tokens on the
// line.
function highlightLine (cm, line, context, forceToEnd) {
  // A styles array always starts with a number identifying the
  // mode/overlays that it is based on (for easy invalidation).
  var st = [cm.state.modeGen]; var lineClasses = {}
  // Compute the base array of styles
  runMode(cm, line.text, cm.doc.mode, context, function (end, style) {
    return st.push(end, style)
  },
  lineClasses, forceToEnd)
  var state = context.state

  // Run overlays, adjust style array.
  var loop = function (o) {
    context.baseTokens = st
    var overlay = cm.state.overlays[o]; var i = 1; var at = 0
    context.state = true
    runMode(cm, line.text, overlay.mode, context, function (end, style) {
      var start = i
      // Ensure there's a token end at the current position, and that i points at it
      while (at < end) {
        var i_end = st[i]
        if (i_end > end) {
          st.splice(i, 1, end, st[i + 1], i_end)
        }
        i += 2
        at = Math.min(end, i_end)
      }
      if (!style) {
        return
      }
      if (overlay.opaque) {
        st.splice(start, i - start, end, 'overlay ' + style)
        i = start + 2
      } else {
        for (; start < i; start += 2) {
          var cur = st[start + 1]
          st[start + 1] = (cur ? cur + ' ' : '') + 'overlay ' + style
        }
      }
    }, lineClasses)
    context.state = state
    context.baseTokens = null
    context.baseTokenPos = 1
  }

  for (var o = 0; o < cm.state.overlays.length; ++o) loop(o)

  return { styles: st, classes: lineClasses.bgClass || lineClasses.textClass ? lineClasses : null }
}

function getLineStyles (cm, line, updateFrontier) {
  if (!line.styles || line.styles[0] != cm.state.modeGen) {
    var context = getContextBefore(cm, lineNo(line))
    var resetState = line.text.length > cm.options.maxHighlightLength && copyState(cm.doc.mode, context.state)
    var result = highlightLine(cm, line, context)
    if (resetState) {
      context.state = resetState
    }
    line.stateAfter = context.save(!resetState)
    line.styles = result.styles
    if (result.classes) {
      line.styleClasses = result.classes
    } else if (line.styleClasses) {
      line.styleClasses = null
    }
    if (updateFrontier === cm.doc.highlightFrontier) {
      cm.doc.modeFrontier = Math.max(cm.doc.modeFrontier, ++cm.doc.highlightFrontier)
    }
  }
  return line.styles
}

function getContextBefore (cm, n, precise) {
  var doc = cm.doc; var display = cm.display
  if (!doc.mode.startState) {
    return new Context(doc, true, n)
  }
  var start = findStartLine(cm, n, precise)
  var saved = start > doc.first && getLine(doc, start - 1).stateAfter
  var context = saved ? Context.fromSaved(doc, saved, start) : new Context(doc, startState(doc.mode), start)

  doc.iter(start, n, function (line) {
    processLine(cm, line.text, context)
    var pos = context.line
    line.stateAfter = pos == n - 1 || pos % 5 == 0 || pos >= display.viewFrom && pos < display.viewTo ? context.save() : null
    context.nextLine()
  })
  if (precise) {
    doc.modeFrontier = context.line
  }
  return context
}

// Lightweight form of highlight -- proceed over this line and
// update state, but don't save a style array. Used for lines that
// aren't currently visible.
function processLine (cm, text, context, startAt) {
  var mode = cm.doc.mode
  var stream = new StringStream(text, cm.options.tabSize, context)
  stream.start = stream.pos = startAt || 0
  if (text == '') {
    callBlankLine(mode, context.state)
  }
  while (!stream.eol()) {
    readToken(mode, stream, context.state)
    stream.start = stream.pos
  }
}

function callBlankLine (mode, state) {
  if (mode.blankLine) {
    return mode.blankLine(state)
  }
  if (!mode.innerMode) {
    return
  }
  var inner = innerMode(mode, state)
  if (inner.mode.blankLine) {
    return inner.mode.blankLine(inner.state)
  }
}

function readToken (mode, stream, state, inner) {
  for (var i = 0; i < 10; i++) {
    if (inner) {
      inner[0] = innerMode(mode, state).mode
    }
    var style = mode.token(stream, state)
    if (stream.pos > stream.start) {
      return style
    }
  }
  throw new Error('Mode ' + mode.name + ' failed to advance stream.')
}

var Token = function (stream, type, state) {
  this.start = stream.start
  this.end = stream.pos
  this.string = stream.current()
  this.type = type || null
  this.state = state
}

// Utility for getTokenAt and getLineTokens
function takeToken (cm, pos, precise, asArray) {
  var doc = cm.doc; var mode = doc.mode; var style
  pos = clipPos(doc, pos)
  var line = getLine(doc, pos.line); var context = getContextBefore(cm, pos.line, precise)
  var stream = new StringStream(line.text, cm.options.tabSize, context); var tokens
  if (asArray) {
    tokens = []
  }
  while ((asArray || stream.pos < pos.ch) && !stream.eol()) {
    stream.start = stream.pos
    style = readToken(mode, stream, context.state)
    if (asArray) {
      tokens.push(new Token(stream, style, copyState(doc.mode, context.state)))
    }
  }
  return asArray ? tokens : new Token(stream, style, context.state)
}

function extractLineClasses (type, output) {
  if (type) {
    for (; ;) {
      var lineClass = type.match(/(?:^|\s+)line-(background-)?(\S+)/)
      if (!lineClass) {
        break
      }
      type = type.slice(0, lineClass.index) + type.slice(lineClass.index + lineClass[0].length)
      var prop = lineClass[1] ? 'bgClass' : 'textClass'
      if (output[prop] == null) {
        output[prop] = lineClass[2]
      } else if (!(new RegExp('(?:^|\s)' + lineClass[2] + '(?:$|\s)')).test(output[prop])) {
        output[prop] += ' ' + lineClass[2]
      }
    }
  }
  return type
}

// Run the given mode's parser over a line, calling f for each token.
function runMode (cm, text, mode, context, f, lineClasses, forceToEnd) {
  var flattenSpans = mode.flattenSpans
  if (flattenSpans == null) {
    flattenSpans = cm.options.flattenSpans
  }
  var curStart = 0; var curStyle = null
  var stream = new StringStream(text, cm.options.tabSize, context); var style
  var inner = cm.options.addModeClass && [null]
  if (text == '') {
    extractLineClasses(callBlankLine(mode, context.state), lineClasses)
  }
  while (!stream.eol()) {
    if (stream.pos > cm.options.maxHighlightLength) {
      flattenSpans = false
      if (forceToEnd) {
        processLine(cm, text, context, stream.pos)
      }
      stream.pos = text.length
      style = null
    } else {
      style = extractLineClasses(readToken(mode, stream, context.state, inner), lineClasses)
    }
    if (inner) {
      var mName = inner[0].name
      if (mName) {
        style = 'm-' + (style ? mName + ' ' + style : mName)
      }
    }
    if (!flattenSpans || curStyle != style) {
      while (curStart < stream.start) {
        curStart = Math.min(stream.start, curStart + 5000)
        f(curStart, curStyle)
      }
      curStyle = style
    }
    stream.start = stream.pos
  }
  while (curStart < stream.pos) {
    // Webkit seems to refuse to render text nodes longer than 57444
    // characters, and returns inaccurate measurements in nodes
    // starting around 5000 chars.
    var pos = Math.min(stream.pos, curStart + 5000)
    f(pos, curStyle)
    curStart = pos
  }
}

// Finds the line to start with when starting a parse. Tries to
// find a line with a stateAfter, so that it can start with a
// valid state. If that fails, it returns the line with the
// smallest indentation, which tends to need the least context to
// parse correctly.
function findStartLine (cm, n, precise) {
  var minindent; var minline; var doc = cm.doc
  var lim = precise ? -1 : n - (cm.doc.mode.innerMode ? 1000 : 100)
  for (var search = n; search > lim; --search) {
    if (search <= doc.first) {
      return doc.first
    }
    var line = getLine(doc, search - 1); var after = line.stateAfter
    if (after && (!precise || search + (after instanceof SavedContext ? after.lookAhead : 0) <= doc.modeFrontier)) {
      return search
    }
    var indented = countColumn(line.text, null, cm.options.tabSize)
    if (minline == null || minindent > indented) {
      minline = search - 1
      minindent = indented
    }
  }
  return minline
}

function retreatFrontier (doc, n) {
  doc.modeFrontier = Math.min(doc.modeFrontier, n)
  if (doc.highlightFrontier < n - 10) {
    return
  }
  var start = doc.first
  for (var line = n - 1; line > start; line--) {
    var saved = getLine(doc, line).stateAfter
    // change is on 3
    // state on line 1 looked ahead 2 -- so saw 3
    // test 1 + 2 < 3 should cover this
    if (saved && (!(saved instanceof SavedContext) || line + saved.lookAhead < n)) {
      start = line + 1
      break
    }
  }
  doc.highlightFrontier = Math.min(doc.highlightFrontier, start)
}

// Optimize some code when these features are not used.
var sawReadOnlySpans = false; var sawCollapsedSpans = false

function seeReadOnlySpans () {
  sawReadOnlySpans = true
}

function seeCollapsedSpans () {
  sawCollapsedSpans = true
}

// TEXTMARKER SPANS

function MarkedSpan (marker, from, to) {
  this.marker = marker
  this.from = from
  this.to = to
}

// Search an array of spans for a span matching the given marker.
function getMarkedSpanFor (spans, marker) {
  if (spans) {
    for (var i = 0; i < spans.length; ++i) {
      var span = spans[i]
      if (span.marker == marker) {
        return span
      }
    }
  }
}

// Remove a span from an array, returning undefined if no spans are
// left (we don't store arrays for lines without spans).
function removeMarkedSpan (spans, span) {
  var r
  for (var i = 0; i < spans.length; ++i) {
    if (spans[i] != span) {
      (r || (r = [])).push(spans[i])
    }
  }
  return r
}

// Add a span to a line.
function addMarkedSpan (line, span) {
  line.markedSpans = line.markedSpans ? line.markedSpans.concat([span]) : [span]
  span.marker.attachLine(line)
}

// Used for the algorithm that adjusts markers for a change in the
// document. These functions cut an array of spans at a given
// character position, returning an array of remaining chunks (or
// undefined if nothing remains).
function markedSpansBefore (old, startCh, isInsert) {
  var nw
  if (old) {
    for (var i = 0; i < old.length; ++i) {
      var span = old[i]; var marker = span.marker
      var startsBefore = span.from == null || (marker.inclusiveLeft ? span.from <= startCh : span.from < startCh)
      if (startsBefore || span.from == startCh && marker.type == 'bookmark' && (!isInsert || !span.marker.insertLeft)) {
        var endsAfter = span.to == null || (marker.inclusiveRight ? span.to >= startCh : span.to > startCh)
                ;(nw || (nw = [])).push(new MarkedSpan(marker, span.from, endsAfter ? null : span.to))
      }
    }
  }
  return nw
}

function markedSpansAfter (old, endCh, isInsert) {
  var nw
  if (old) {
    for (var i = 0; i < old.length; ++i) {
      var span = old[i]; var marker = span.marker
      var endsAfter = span.to == null || (marker.inclusiveRight ? span.to >= endCh : span.to > endCh)
      if (endsAfter || span.from == endCh && marker.type == 'bookmark' && (!isInsert || span.marker.insertLeft)) {
        var startsBefore = span.from == null || (marker.inclusiveLeft ? span.from <= endCh : span.from < endCh)
                ;(nw || (nw = [])).push(new MarkedSpan(marker, startsBefore ? null : span.from - endCh,
          span.to == null ? null : span.to - endCh))
      }
    }
  }
  return nw
}

// Given a change object, compute the new set of marker spans that
// cover the line in which the change took place. Removes spans
// entirely within the change, reconnects spans belonging to the
// same marker that appear on both sides of the change, and cuts off
// spans partially within the change. Returns an array of span
// arrays with one element for each line in (after) the change.
function stretchSpansOverChange (doc, change) {
  if (change.full) {
    return null
  }
  var oldFirst = isLine(doc, change.from.line) && getLine(doc, change.from.line).markedSpans
  var oldLast = isLine(doc, change.to.line) && getLine(doc, change.to.line).markedSpans
  if (!oldFirst && !oldLast) {
    return null
  }

  var startCh = change.from.ch; var endCh = change.to.ch; var isInsert = cmp(change.from, change.to) == 0
  // Get the spans that 'stick out' on both sides
  var first = markedSpansBefore(oldFirst, startCh, isInsert)
  var last = markedSpansAfter(oldLast, endCh, isInsert)

  // Next, merge those two ends
  var sameLine = change.text.length == 1; var offset = lst(change.text).length + (sameLine ? startCh : 0)
  if (first) {
    // Fix up .to properties of first
    for (var i = 0; i < first.length; ++i) {
      var span = first[i]
      if (span.to == null) {
        var found = getMarkedSpanFor(last, span.marker)
        if (!found) {
          span.to = startCh
        } else if (sameLine) {
          span.to = found.to == null ? null : found.to + offset
        }
      }
    }
  }
  if (last) {
    // Fix up .from in last (or move them into first in case of sameLine)
    for (var i$1 = 0; i$1 < last.length; ++i$1) {
      var span$1 = last[i$1]
      if (span$1.to != null) {
        span$1.to += offset
      }
      if (span$1.from == null) {
        var found$1 = getMarkedSpanFor(first, span$1.marker)
        if (!found$1) {
          span$1.from = offset
          if (sameLine) {
            (first || (first = [])).push(span$1)
          }
        }
      } else {
        span$1.from += offset
        if (sameLine) {
          (first || (first = [])).push(span$1)
        }
      }
    }
  }
  // Make sure we didn't create any zero-length spans
  if (first) {
    first = clearEmptySpans(first)
  }
  if (last && last != first) {
    last = clearEmptySpans(last)
  }

  var newMarkers = [first]
  if (!sameLine) {
    // Fill gap with whole-line-spans
    var gap = change.text.length - 2; var gapMarkers
    if (gap > 0 && first) {
      for (var i$2 = 0; i$2 < first.length; ++i$2) {
        if (first[i$2].to == null) {
          (gapMarkers || (gapMarkers = [])).push(new MarkedSpan(first[i$2].marker, null, null))
        }
      }
    }
    for (var i$3 = 0; i$3 < gap; ++i$3) {
      newMarkers.push(gapMarkers)
    }
    newMarkers.push(last)
  }
  return newMarkers
}

// Remove spans that are empty and don't have a clearWhenEmpty
// option of false.
function clearEmptySpans (spans) {
  for (var i = 0; i < spans.length; ++i) {
    var span = spans[i]
    if (span.from != null && span.from == span.to && span.marker.clearWhenEmpty !== false) {
      spans.splice(i--, 1)
    }
  }
  if (!spans.length) {
    return null
  }
  return spans
}

// Used to 'clip' out readOnly ranges when making a change.
function removeReadOnlyRanges (doc, from, to) {
  var markers = null
  doc.iter(from.line, to.line + 1, function (line) {
    if (line.markedSpans) {
      for (var i = 0; i < line.markedSpans.length; ++i) {
        var mark = line.markedSpans[i].marker
        if (mark.readOnly && (!markers || indexOf(markers, mark) == -1)) {
          (markers || (markers = [])).push(mark)
        }
      }
    }
  })
  if (!markers) {
    return null
  }
  var parts = [{ from: from, to: to }]
  for (var i = 0; i < markers.length; ++i) {
    var mk = markers[i]; var m = mk.find(0)
    for (var j = 0; j < parts.length; ++j) {
      var p = parts[j]
      if (cmp(p.to, m.from) < 0 || cmp(p.from, m.to) > 0) {
        continue
      }
      var newParts = [j, 1]; var dfrom = cmp(p.from, m.from); var dto = cmp(p.to, m.to)
      if (dfrom < 0 || !mk.inclusiveLeft && !dfrom) {
        newParts.push({ from: p.from, to: m.from })
      }
      if (dto > 0 || !mk.inclusiveRight && !dto) {
        newParts.push({ from: m.to, to: p.to })
      }
      parts.splice.apply(parts, newParts)
      j += newParts.length - 3
    }
  }
  return parts
}

// Connect or disconnect spans from a line.
function detachMarkedSpans (line) {
  var spans = line.markedSpans
  if (!spans) {
    return
  }
  for (var i = 0; i < spans.length; ++i) {
    spans[i].marker.detachLine(line)
  }
  line.markedSpans = null
}

function attachMarkedSpans (line, spans) {
  if (!spans) {
    return
  }
  for (var i = 0; i < spans.length; ++i) {
    spans[i].marker.attachLine(line)
  }
  line.markedSpans = spans
}

// Helpers used when computing which overlapping collapsed span
// counts as the larger one.
function extraLeft (marker) {
  return marker.inclusiveLeft ? -1 : 0
}

function extraRight (marker) {
  return marker.inclusiveRight ? 1 : 0
}

// Returns a number indicating which of two overlapping collapsed
// spans is larger (and thus includes the other). Falls back to
// comparing ids when the spans cover exactly the same range.
function compareCollapsedMarkers (a, b) {
  var lenDiff = a.lines.length - b.lines.length
  if (lenDiff != 0) {
    return lenDiff
  }
  var aPos = a.find(); var bPos = b.find()
  var fromCmp = cmp(aPos.from, bPos.from) || extraLeft(a) - extraLeft(b)
  if (fromCmp) {
    return -fromCmp
  }
  var toCmp = cmp(aPos.to, bPos.to) || extraRight(a) - extraRight(b)
  if (toCmp) {
    return toCmp
  }
  return b.id - a.id
}

// Find out whether a line ends or starts in a collapsed span. If
// so, return the marker for that span.
function collapsedSpanAtSide (line, start) {
  var sps = sawCollapsedSpans && line.markedSpans; var found
  if (sps) {
    for (var sp = (void 0), i = 0; i < sps.length; ++i) {
      sp = sps[i]
      if (sp.marker.collapsed && (start ? sp.from : sp.to) == null &&
                (!found || compareCollapsedMarkers(found, sp.marker) < 0)) {
        found = sp.marker
      }
    }
  }
  return found
}

function collapsedSpanAtStart (line) {
  return collapsedSpanAtSide(line, true)
}

function collapsedSpanAtEnd (line) {
  return collapsedSpanAtSide(line, false)
}

function collapsedSpanAround (line, ch) {
  var sps = sawCollapsedSpans && line.markedSpans; var found
  if (sps) {
    for (var i = 0; i < sps.length; ++i) {
      var sp = sps[i]
      if (sp.marker.collapsed && (sp.from == null || sp.from < ch) && (sp.to == null || sp.to > ch) &&
                (!found || compareCollapsedMarkers(found, sp.marker) < 0)) {
        found = sp.marker
      }
    }
  }
  return found
}

// Test whether there exists a collapsed span that partially
// overlaps (covers the start or end, but not both) of a new span.
// Such overlap is not allowed.
function conflictingCollapsedRange (doc, lineNo$$1, from, to, marker) {
  var line = getLine(doc, lineNo$$1)
  var sps = sawCollapsedSpans && line.markedSpans
  if (sps) {
    for (var i = 0; i < sps.length; ++i) {
      var sp = sps[i]
      if (!sp.marker.collapsed) {
        continue
      }
      var found = sp.marker.find(0)
      var fromCmp = cmp(found.from, from) || extraLeft(sp.marker) - extraLeft(marker)
      var toCmp = cmp(found.to, to) || extraRight(sp.marker) - extraRight(marker)
      if (fromCmp >= 0 && toCmp <= 0 || fromCmp <= 0 && toCmp >= 0) {
        continue
      }
      if (fromCmp <= 0 && (sp.marker.inclusiveRight && marker.inclusiveLeft ? cmp(found.to, from) >= 0 : cmp(found.to, from) > 0) ||
                fromCmp >= 0 && (sp.marker.inclusiveRight && marker.inclusiveLeft ? cmp(found.from, to) <= 0 : cmp(found.from, to) < 0)) {
        return true
      }
    }
  }
}

// A visual line is a line as drawn on the screen. Folding, for
// example, can cause multiple logical lines to appear on the same
// visual line. This finds the start of the visual line that the
// given line is part of (usually that is the line itself).
function visualLine (line) {
  var merged
  while (merged = collapsedSpanAtStart(line)) {
    line = merged.find(-1, true).line
  }
  return line
}

function visualLineEnd (line) {
  var merged
  while (merged = collapsedSpanAtEnd(line)) {
    line = merged.find(1, true).line
  }
  return line
}

// Returns an array of logical lines that continue the visual line
// started by the argument, or undefined if there are no such lines.
function visualLineContinued (line) {
  var merged, lines
  while (merged = collapsedSpanAtEnd(line)) {
    line = merged.find(1, true).line
    ;(lines || (lines = [])).push(line)
  }
  return lines
}

// Get the line number of the start of the visual line that the
// given line number is part of.
function visualLineNo (doc, lineN) {
  var line = getLine(doc, lineN); var vis = visualLine(line)
  if (line == vis) {
    return lineN
  }
  return lineNo(vis)
}

// Get the line number of the start of the next visual line after
// the given line.
function visualLineEndNo (doc, lineN) {
  if (lineN > doc.lastLine()) {
    return lineN
  }
  var line = getLine(doc, lineN); var merged
  if (!lineIsHidden(doc, line)) {
    return lineN
  }
  while (merged = collapsedSpanAtEnd(line)) {
    line = merged.find(1, true).line
  }
  return lineNo(line) + 1
}

// Compute whether a line is hidden. Lines count as hidden when they
// are part of a visual line that starts with another line, or when
// they are entirely covered by collapsed, non-widget span.
function lineIsHidden (doc, line) {
  var sps = sawCollapsedSpans && line.markedSpans
  if (sps) {
    for (var sp = (void 0), i = 0; i < sps.length; ++i) {
      sp = sps[i]
      if (!sp.marker.collapsed) {
        continue
      }
      if (sp.from == null) {
        return true
      }
      if (sp.marker.widgetNode) {
        continue
      }
      if (sp.from == 0 && sp.marker.inclusiveLeft && lineIsHiddenInner(doc, line, sp)) {
        return true
      }
    }
  }
}

function lineIsHiddenInner (doc, line, span) {
  if (span.to == null) {
    var end = span.marker.find(1, true)
    return lineIsHiddenInner(doc, end.line, getMarkedSpanFor(end.line.markedSpans, span.marker))
  }
  if (span.marker.inclusiveRight && span.to == line.text.length) {
    return true
  }
  for (var sp = (void 0), i = 0; i < line.markedSpans.length; ++i) {
    sp = line.markedSpans[i]
    if (sp.marker.collapsed && !sp.marker.widgetNode && sp.from == span.to &&
            (sp.to == null || sp.to != span.from) &&
            (sp.marker.inclusiveLeft || span.marker.inclusiveRight) &&
            lineIsHiddenInner(doc, line, sp)) {
      return true
    }
  }
}

// Find the height above the given line.
function heightAtLine (lineObj) {
  lineObj = visualLine(lineObj)

  var h = 0; var chunk = lineObj.parent
  for (var i = 0; i < chunk.lines.length; ++i) {
    var line = chunk.lines[i]
    if (line == lineObj) {
      break
    } else {
      h += line.height
    }
  }
  for (var p = chunk.parent; p; chunk = p, p = chunk.parent) {
    for (var i$1 = 0; i$1 < p.children.length; ++i$1) {
      var cur = p.children[i$1]
      if (cur == chunk) {
        break
      } else {
        h += cur.height
      }
    }
  }
  return h
}

// Compute the character length of a line, taking into account
// collapsed ranges (see markText) that might hide parts, and join
// other lines onto it.
function lineLength (line) {
  if (line.height == 0) {
    return 0
  }
  var len = line.text.length; var merged; var cur = line
  while (merged = collapsedSpanAtStart(cur)) {
    var found = merged.find(0, true)
    cur = found.from.line
    len += found.from.ch - found.to.ch
  }
  cur = line
  while (merged = collapsedSpanAtEnd(cur)) {
    var found$1 = merged.find(0, true)
    len -= cur.text.length - found$1.from.ch
    cur = found$1.to.line
    len += cur.text.length - found$1.to.ch
  }
  return len
}

// Find the longest line in the document.
function findMaxLine (cm) {
  var d = cm.display; var doc = cm.doc
  d.maxLine = getLine(doc, doc.first)
  d.maxLineLength = lineLength(d.maxLine)
  d.maxLineChanged = true
  doc.iter(function (line) {
    var len = lineLength(line)
    if (len > d.maxLineLength) {
      d.maxLineLength = len
      d.maxLine = line
    }
  })
}

// LINE DATA STRUCTURE

// Line objects. These hold state related to a line, including
// highlighting info (the styles array).
var Line = function (text, markedSpans, estimateHeight) {
  this.text = text
  attachMarkedSpans(this, markedSpans)
  this.height = estimateHeight ? estimateHeight(this) : 1
}

Line.prototype.lineNo = function () {
  return lineNo(this)
}
eventMixin(Line)

// Change the content (text, markers) of a line. Automatically
// invalidates cached information and tries to re-estimate the
// line's height.
function updateLine (line, text, markedSpans, estimateHeight) {
  line.text = text
  if (line.stateAfter) {
    line.stateAfter = null
  }
  if (line.styles) {
    line.styles = null
  }
  if (line.order != null) {
    line.order = null
  }
  detachMarkedSpans(line)
  attachMarkedSpans(line, markedSpans)
  var estHeight = estimateHeight ? estimateHeight(line) : 1
  if (estHeight != line.height) {
    updateLineHeight(line, estHeight)
  }
}

// Detach a line from the document tree and its markers.
function cleanUpLine (line) {
  line.parent = null
  detachMarkedSpans(line)
}

// Convert a style as returned by a mode (either null, or a string
// containing one or more styles) to a CSS style. This is cached,
// and also looks for line-wide styles.
var styleToClassCache = {}; var styleToClassCacheWithMode = {}

function interpretTokenStyle (style, options) {
  if (!style || /^\s*$/.test(style)) {
    return null
  }
  var cache = options.addModeClass ? styleToClassCacheWithMode : styleToClassCache
  return cache[style] ||
        (cache[style] = style.replace(/\S+/g, 'cm-$&'))
}

// Render the DOM representation of the text of a line. Also builds
// up a 'line map', which points at the DOM nodes that represent
// specific stretches of text, and is used by the measuring code.
// The returned object contains the DOM node, this map, and
// information about line-wide styles that were set by the mode.
function buildLineContent (cm, lineView) {
  // The padding-right forces the element to have a 'border', which
  // is needed on Webkit to be able to get line-level bounding
  // rectangles for it (in measureChar).
  var content = eltP('span', null, null, webkit ? 'padding-right: .1px' : null)
  var builder = {
    pre: eltP('pre', [content], 'CodeMirror-line'),
    content: content,
    col: 0,
    pos: 0,
    cm: cm,
    trailingSpace: false,
    splitSpaces: cm.getOption('lineWrapping')
  }
  lineView.measure = {}

  // Iterate over the logical lines that make up this visual line.
  for (var i = 0; i <= (lineView.rest ? lineView.rest.length : 0); i++) {
    var line = i ? lineView.rest[i - 1] : lineView.line; var order = (void 0)
    builder.pos = 0
    builder.addToken = buildToken
    // Optionally wire in some hacks into the token-rendering
    // algorithm, to deal with browser quirks.
    if (hasBadBidiRects(cm.display.measure) && (order = getOrder(line, cm.doc.direction))) {
      builder.addToken = buildTokenBadBidi(builder.addToken, order)
    }
    builder.map = []
    var allowFrontierUpdate = lineView != cm.display.externalMeasured && lineNo(line)
    insertLineContent(line, builder, getLineStyles(cm, line, allowFrontierUpdate))
    if (line.styleClasses) {
      if (line.styleClasses.bgClass) {
        builder.bgClass = joinClasses(line.styleClasses.bgClass, builder.bgClass || '')
      }
      if (line.styleClasses.textClass) {
        builder.textClass = joinClasses(line.styleClasses.textClass, builder.textClass || '')
      }
    }

    // Ensure at least a single node is present, for measuring.
    if (builder.map.length == 0) {
      builder.map.push(0, 0, builder.content.appendChild(zeroWidthElement(cm.display.measure)))
    }

    // Store the map and a cache object for the current logical line
    if (i == 0) {
      lineView.measure.map = builder.map
      lineView.measure.cache = {}
    } else {
      (lineView.measure.maps || (lineView.measure.maps = [])).push(builder.map)
      ;(lineView.measure.caches || (lineView.measure.caches = [])).push({})
    }
  }

  // See issue #2901
  if (webkit) {
    var last = builder.content.lastChild
    if (/\bcm-tab\b/.test(last.className) || (last.querySelector && last.querySelector('.cm-tab'))) {
      builder.content.className = 'cm-tab-wrap-hack'
    }
  }

  signal(cm, 'renderLine', cm, lineView.line, builder.pre)
  if (builder.pre.className) {
    builder.textClass = joinClasses(builder.pre.className, builder.textClass || '')
  }

  return builder
}

function defaultSpecialCharPlaceholder (ch) {
  var token = elt('span', '\u2022', 'cm-invalidchar')
  token.title = '\\u' + ch.charCodeAt(0).toString(16)
  token.setAttribute('aria-label', token.title)
  return token
}

// Build up the DOM representation for a single token, and add it to
// the line map. Takes care to render special characters separately.
function buildToken (builder, text, style, startStyle, endStyle, css, attributes) {
  if (!text) {
    return
  }
  var displayText = builder.splitSpaces ? splitSpaces(text, builder.trailingSpace) : text
  var special = builder.cm.state.specialChars; var mustWrap = false
  var content
  if (!special.test(text)) {
    builder.col += text.length
    content = document.createTextNode(displayText)
    builder.map.push(builder.pos, builder.pos + text.length, content)
    if (ie && ie_version < 9) {
      mustWrap = true
    }
    builder.pos += text.length
  } else {
    content = document.createDocumentFragment()
    var pos = 0
    while (true) {
      special.lastIndex = pos
      var m = special.exec(text)
      var skipped = m ? m.index - pos : text.length - pos
      if (skipped) {
        var txt = document.createTextNode(displayText.slice(pos, pos + skipped))
        if (ie && ie_version < 9) {
          content.appendChild(elt('span', [txt]))
        } else {
          content.appendChild(txt)
        }
        builder.map.push(builder.pos, builder.pos + skipped, txt)
        builder.col += skipped
        builder.pos += skipped
      }
      if (!m) {
        break
      }
      pos += skipped + 1
      var txt$1 = (void 0)
      if (m[0] == '\t') {
        var tabSize = builder.cm.options.tabSize; var tabWidth = tabSize - builder.col % tabSize
        txt$1 = content.appendChild(elt('span', spaceStr(tabWidth), 'cm-tab'))
        txt$1.setAttribute('role', 'presentation')
        txt$1.setAttribute('cm-text', '\t')
        builder.col += tabWidth
      } else if (m[0] == '\r' || m[0] == '\n') {
        txt$1 = content.appendChild(elt('span', m[0] == '\r' ? '\u240d' : '\u2424', 'cm-invalidchar'))
        txt$1.setAttribute('cm-text', m[0])
        builder.col += 1
      } else {
        txt$1 = builder.cm.options.specialCharPlaceholder(m[0])
        txt$1.setAttribute('cm-text', m[0])
        if (ie && ie_version < 9) {
          content.appendChild(elt('span', [txt$1]))
        } else {
          content.appendChild(txt$1)
        }
        builder.col += 1
      }
      builder.map.push(builder.pos, builder.pos + 1, txt$1)
      builder.pos++
    }
  }
  builder.trailingSpace = displayText.charCodeAt(text.length - 1) == 32
  if (style || startStyle || endStyle || mustWrap || css) {
    var fullStyle = style || ''
    if (startStyle) {
      fullStyle += startStyle
    }
    if (endStyle) {
      fullStyle += endStyle
    }
    var token = elt('span', [content], fullStyle, css)
    if (attributes) {
      for (var attr in attributes) {
        if (attributes.hasOwnProperty(attr) && attr != 'style' && attr != 'class') {
          token.setAttribute(attr, attributes[attr])
        }
      }
    }
    return builder.content.appendChild(token)
  }
  builder.content.appendChild(content)
}

// Change some spaces to NBSP to prevent the browser from collapsing
// trailing spaces at the end of a line when rendering text (issue #1362).
function splitSpaces (text, trailingBefore) {
  if (text.length > 1 && !/ {2}/.test(text)) {
    return text
  }
  var spaceBefore = trailingBefore; var result = ''
  for (var i = 0; i < text.length; i++) {
    var ch = text.charAt(i)
    if (ch == ' ' && spaceBefore && (i == text.length - 1 || text.charCodeAt(i + 1) == 32)) {
      ch = '\u00a0'
    }
    result += ch
    spaceBefore = ch == ' '
  }
  return result
}

// Work around nonsense dimensions being reported for stretches of
// right-to-left text.
function buildTokenBadBidi (inner, order) {
  return function (builder, text, style, startStyle, endStyle, css, attributes) {
    style = style ? style + ' cm-force-border' : 'cm-force-border'
    var start = builder.pos; var end = start + text.length
    for (; ;) {
      // Find the part that overlaps with the start of this text
      var part = (void 0)
      for (var i = 0; i < order.length; i++) {
        part = order[i]
        if (part.to > start && part.from <= start) {
          break
        }
      }
      if (part.to >= end) {
        return inner(builder, text, style, startStyle, endStyle, css, attributes)
      }
      inner(builder, text.slice(0, part.to - start), style, startStyle, null, css, attributes)
      startStyle = null
      text = text.slice(part.to - start)
      start = part.to
    }
  }
}

function buildCollapsedSpan (builder, size, marker, ignoreWidget) {
  var widget = !ignoreWidget && marker.widgetNode
  if (widget) {
    builder.map.push(builder.pos, builder.pos + size, widget)
  }
  if (!ignoreWidget && builder.cm.display.input.needsContentAttribute) {
    if (!widget) {
      widget = builder.content.appendChild(document.createElement('span'))
    }
    widget.setAttribute('cm-marker', marker.id)
  }
  if (widget) {
    builder.cm.display.input.setUneditable(widget)
    builder.content.appendChild(widget)
  }
  builder.pos += size
  builder.trailingSpace = false
}

// Outputs a number of spans to make up a line, taking highlighting
// and index text into account.
function insertLineContent (line, builder, styles) {
  var spans = line.markedSpans; var allText = line.text; var at = 0
  if (!spans) {
    for (var i$1 = 1; i$1 < styles.length; i$1 += 2) {
      builder.addToken(builder, allText.slice(at, at = styles[i$1]), interpretTokenStyle(styles[i$1 + 1], builder.cm.options))
    }
    return
  }

  var len = allText.length; var pos = 0; var i = 1; var text = ''; var style; var css
  var nextChange = 0; var spanStyle; var spanEndStyle; var spanStartStyle; var collapsed; var attributes
  for (; ;) {
    if (nextChange == pos) { // Update current marker set
      spanStyle = spanEndStyle = spanStartStyle = css = ''
      attributes = null
      collapsed = null
      nextChange = Infinity
      var foundBookmarks = []; var endStyles = (void 0)
      for (var j = 0; j < spans.length; ++j) {
        var sp = spans[j]; var m = sp.marker
        if (m.type == 'bookmark' && sp.from == pos && m.widgetNode) {
          foundBookmarks.push(m)
        } else if (sp.from <= pos && (sp.to == null || sp.to > pos || m.collapsed && sp.to == pos && sp.from == pos)) {
          if (sp.to != null && sp.to != pos && nextChange > sp.to) {
            nextChange = sp.to
            spanEndStyle = ''
          }
          if (m.className) {
            spanStyle += ' ' + m.className
          }
          if (m.css) {
            css = (css ? css + ';' : '') + m.css
          }
          if (m.startStyle && sp.from == pos) {
            spanStartStyle += ' ' + m.startStyle
          }
          if (m.endStyle && sp.to == nextChange) {
            (endStyles || (endStyles = [])).push(m.endStyle, sp.to)
          }
          // support for the old title property
          // https://github.com/codemirror/CodeMirror/pull/5673
          if (m.title) {
            (attributes || (attributes = {})).title = m.title
          }
          if (m.attributes) {
            for (var attr in m.attributes) {
              (attributes || (attributes = {}))[attr] = m.attributes[attr]
            }
          }
          if (m.collapsed && (!collapsed || compareCollapsedMarkers(collapsed.marker, m) < 0)) {
            collapsed = sp
          }
        } else if (sp.from > pos && nextChange > sp.from) {
          nextChange = sp.from
        }
      }
      if (endStyles) {
        for (var j$1 = 0; j$1 < endStyles.length; j$1 += 2) {
          if (endStyles[j$1 + 1] == nextChange) {
            spanEndStyle += ' ' + endStyles[j$1]
          }
        }
      }

      if (!collapsed || collapsed.from == pos) {
        for (var j$2 = 0; j$2 < foundBookmarks.length; ++j$2) {
          buildCollapsedSpan(builder, 0, foundBookmarks[j$2])
        }
      }
      if (collapsed && (collapsed.from || 0) == pos) {
        buildCollapsedSpan(builder, (collapsed.to == null ? len + 1 : collapsed.to) - pos,
          collapsed.marker, collapsed.from == null)
        if (collapsed.to == null) {
          return
        }
        if (collapsed.to == pos) {
          collapsed = false
        }
      }
    }
    if (pos >= len) {
      break
    }

    var upto = Math.min(len, nextChange)
    while (true) {
      if (text) {
        var end = pos + text.length
        if (!collapsed) {
          var tokenText = end > upto ? text.slice(0, upto - pos) : text
          builder.addToken(builder, tokenText, style ? style + spanStyle : spanStyle,
            spanStartStyle, pos + tokenText.length == nextChange ? spanEndStyle : '', css, attributes)
        }
        if (end >= upto) {
          text = text.slice(upto - pos)
          pos = upto
          break
        }
        pos = end
        spanStartStyle = ''
      }
      text = allText.slice(at, at = styles[i++])
      style = interpretTokenStyle(styles[i++], builder.cm.options)
    }
  }
}

// These objects are used to represent the visible (currently drawn)
// part of the document. A LineView may correspond to multiple
// logical lines, if those are connected by collapsed ranges.
function LineView (doc, line, lineN) {
  // The starting line
  this.line = line
  // Continuing lines, if any
  this.rest = visualLineContinued(line)
  // Number of logical lines in this visual line
  this.size = this.rest ? lineNo(lst(this.rest)) - lineN + 1 : 1
  this.node = this.text = null
  this.hidden = lineIsHidden(doc, line)
}

// Create a range of LineView objects for the given lines.
function buildViewArray (cm, from, to) {
  var array = []; var nextPos
  for (var pos = from; pos < to; pos = nextPos) {
    var view = new LineView(cm.doc, getLine(cm.doc, pos), pos)
    nextPos = pos + view.size
    array.push(view)
  }
  return array
}

var operationGroup = null

function pushOperation (op) {
  if (operationGroup) {
    operationGroup.ops.push(op)
  } else {
    op.ownsGroup = operationGroup = {
      ops: [op],
      delayedCallbacks: []
    }
  }
}

function fireCallbacksForOps (group) {
  // Calls delayed callbacks and cursorActivity handlers until no
  // new ones appear
  var callbacks = group.delayedCallbacks; var i = 0
  do {
    for (; i < callbacks.length; i++) {
      callbacks[i].call(null)
    }
    for (var j = 0; j < group.ops.length; j++) {
      var op = group.ops[j]
      if (op.cursorActivityHandlers) {
        while (op.cursorActivityCalled < op.cursorActivityHandlers.length) {
          op.cursorActivityHandlers[op.cursorActivityCalled++].call(null, op.cm)
        }
      }
    }
  } while (i < callbacks.length)
}

function finishOperation (op, endCb) {
  var group = op.ownsGroup
  if (!group) {
    return
  }

  try {
    fireCallbacksForOps(group)
  } finally {
    operationGroup = null
    endCb(group)
  }
}

var orphanDelayedCallbacks = null

// Often, we want to signal events at a point where we are in the
// middle of some work, but don't want the handler to start calling
// other methods on the src, which might be in an inconsistent
// state or simply not expect any other events to happen.
// signalLater looks whether there are any handlers, and schedules
// them to be executed when the last operation ends, or, if no
// operation is active, when a timeout fires.
function signalLater (emitter, type /*, values... */) {
  var arr = getHandlers(emitter, type)
  if (!arr.length) {
    return
  }
  var args = Array.prototype.slice.call(arguments, 2); var list
  if (operationGroup) {
    list = operationGroup.delayedCallbacks
  } else if (orphanDelayedCallbacks) {
    list = orphanDelayedCallbacks
  } else {
    list = orphanDelayedCallbacks = []
    setTimeout(fireOrphanDelayed, 0)
  }
  var loop = function (i) {
    list.push(function () {
      return arr[i].apply(null, args)
    })
  }

  for (var i = 0; i < arr.length; ++i) { loop(i) }
}

function fireOrphanDelayed () {
  var delayed = orphanDelayedCallbacks
  orphanDelayedCallbacks = null
  for (var i = 0; i < delayed.length; ++i) {
    delayed[i]()
  }
}

// When an aspect of a line changes, a string is added to
// lineView.changes. This updates the relevant part of the line's
// DOM structure.
function updateLineForChanges (cm, lineView, lineN, dims) {
  for (var j = 0; j < lineView.changes.length; j++) {
    var type = lineView.changes[j]
    if (type == 'text') {
      updateLineText(cm, lineView)
    } else if (type == 'gutter') {
      updateLineGutter(cm, lineView, lineN, dims)
    } else if (type == 'class') {
      updateLineClasses(cm, lineView)
    } else if (type == 'widget') {
      updateLineWidgets(cm, lineView, dims)
    }
  }
  lineView.changes = null
}

// Lines with gutter elements, widgets or a background class need to
// be wrapped, and have the extra elements added to the wrapper div
function ensureLineWrapped (lineView) {
  if (lineView.node == lineView.text) {
    lineView.node = elt('div', null, null, 'position: relative')
    if (lineView.text.parentNode) {
      lineView.text.parentNode.replaceChild(lineView.node, lineView.text)
    }
    lineView.node.appendChild(lineView.text)
    if (ie && ie_version < 8) {
      lineView.node.style.zIndex = 2
    }
  }
  return lineView.node
}

function updateLineBackground (cm, lineView) {
  var cls = lineView.bgClass ? lineView.bgClass + ' ' + (lineView.line.bgClass || '') : lineView.line.bgClass
  if (cls) {
    cls += ' CodeMirror-linebackground'
  }
  if (lineView.background) {
    if (cls) {
      lineView.background.className = cls
    } else {
      lineView.background.parentNode.removeChild(lineView.background)
      lineView.background = null
    }
  } else if (cls) {
    var wrap = ensureLineWrapped(lineView)
    lineView.background = wrap.insertBefore(elt('div', null, cls), wrap.firstChild)
    cm.display.input.setUneditable(lineView.background)
  }
}

// Wrapper around buildLineContent which will reuse the structure
// in display.externalMeasured when possible.
function getLineContent (cm, lineView) {
  var ext = cm.display.externalMeasured
  if (ext && ext.line == lineView.line) {
    cm.display.externalMeasured = null
    lineView.measure = ext.measure
    return ext.built
  }
  return buildLineContent(cm, lineView)
}

// Redraw the line's text. Interacts with the background and text
// classes because the mode may output tokens that influence these
// classes.
function updateLineText (cm, lineView) {
  var cls = lineView.text.className
  var built = getLineContent(cm, lineView)
  if (lineView.text == lineView.node) {
    lineView.node = built.pre
  }
  lineView.text.parentNode.replaceChild(built.pre, lineView.text)
  lineView.text = built.pre
  if (built.bgClass != lineView.bgClass || built.textClass != lineView.textClass) {
    lineView.bgClass = built.bgClass
    lineView.textClass = built.textClass
    updateLineClasses(cm, lineView)
  } else if (cls) {
    lineView.text.className = cls
  }
}

function updateLineClasses (cm, lineView) {
  updateLineBackground(cm, lineView)
  if (lineView.line.wrapClass) {
    ensureLineWrapped(lineView).className = lineView.line.wrapClass
  } else if (lineView.node != lineView.text) {
    lineView.node.className = ''
  }
  var textClass = lineView.textClass ? lineView.textClass + ' ' + (lineView.line.textClass || '') : lineView.line.textClass
  lineView.text.className = textClass || ''
}

function updateLineGutter (cm, lineView, lineN, dims) {
  if (lineView.gutter) {
    lineView.node.removeChild(lineView.gutter)
    lineView.gutter = null
  }
  if (lineView.gutterBackground) {
    lineView.node.removeChild(lineView.gutterBackground)
    lineView.gutterBackground = null
  }
  if (lineView.line.gutterClass) {
    var wrap = ensureLineWrapped(lineView)
    lineView.gutterBackground = elt('div', null, 'CodeMirror-gutter-background ' + lineView.line.gutterClass,
      ('left: ' + (cm.options.fixedGutter ? dims.fixedPos : -dims.gutterTotalWidth) + 'px; width: ' + (dims.gutterTotalWidth) + 'px'))
    cm.display.input.setUneditable(lineView.gutterBackground)
    wrap.insertBefore(lineView.gutterBackground, lineView.text)
  }
  var markers = lineView.line.gutterMarkers
  if (cm.options.lineNumbers || markers) {
    var wrap$1 = ensureLineWrapped(lineView)
    var gutterWrap = lineView.gutter = elt('div', null, 'CodeMirror-gutter-wrapper', ('left: ' + (cm.options.fixedGutter ? dims.fixedPos : -dims.gutterTotalWidth) + 'px'))
    cm.display.input.setUneditable(gutterWrap)
    wrap$1.insertBefore(gutterWrap, lineView.text)
    if (lineView.line.gutterClass) {
      gutterWrap.className += ' ' + lineView.line.gutterClass
    }
    if (cm.options.lineNumbers && (!markers || !markers['CodeMirror-linenumbers'])) {
      lineView.lineNumber = gutterWrap.appendChild(
        elt('div', lineNumberFor(cm.options, lineN),
          'CodeMirror-linenumber CodeMirror-gutter-elt',
          ('left: ' + (dims.gutterLeft['CodeMirror-linenumbers']) + 'px; width: ' + (cm.display.lineNumInnerWidth) + 'px')))
    }
    if (markers) {
      for (var k = 0; k < cm.display.gutterSpecs.length; ++k) {
        var id = cm.display.gutterSpecs[k].className; var found = markers.hasOwnProperty(id) && markers[id]
        if (found) {
          gutterWrap.appendChild(elt('div', [found], 'CodeMirror-gutter-elt',
            ('left: ' + (dims.gutterLeft[id]) + 'px; width: ' + (dims.gutterWidth[id]) + 'px')))
        }
      }
    }
  }
}

function updateLineWidgets (cm, lineView, dims) {
  if (lineView.alignable) {
    lineView.alignable = null
  }
  for (var node = lineView.node.firstChild, next = (void 0); node; node = next) {
    next = node.nextSibling
    if (node.className == 'CodeMirror-linewidget') {
      lineView.node.removeChild(node)
    }
  }
  insertLineWidgets(cm, lineView, dims)
}

// Build a line's DOM representation from scratch
function buildLineElement (cm, lineView, lineN, dims) {
  var built = getLineContent(cm, lineView)
  lineView.text = lineView.node = built.pre
  if (built.bgClass) {
    lineView.bgClass = built.bgClass
  }
  if (built.textClass) {
    lineView.textClass = built.textClass
  }

  updateLineClasses(cm, lineView)
  updateLineGutter(cm, lineView, lineN, dims)
  insertLineWidgets(cm, lineView, dims)
  return lineView.node
}

// A lineView may contain multiple logical lines (when merged by
// collapsed spans). The widgets for all of them need to be drawn.
function insertLineWidgets (cm, lineView, dims) {
  insertLineWidgetsFor(cm, lineView.line, lineView, dims, true)
  if (lineView.rest) {
    for (var i = 0; i < lineView.rest.length; i++) {
      insertLineWidgetsFor(cm, lineView.rest[i], lineView, dims, false)
    }
  }
}

function insertLineWidgetsFor (cm, line, lineView, dims, allowAbove) {
  if (!line.widgets) {
    return
  }
  var wrap = ensureLineWrapped(lineView)
  for (var i = 0, ws = line.widgets; i < ws.length; ++i) {
    var widget = ws[i]; var node = elt('div', [widget.node], 'CodeMirror-linewidget')
    if (!widget.handleMouseEvents) {
      node.setAttribute('cm-ignore-events', 'true')
    }
    positionLineWidget(widget, node, lineView, dims)
    cm.display.input.setUneditable(node)
    if (allowAbove && widget.above) {
      wrap.insertBefore(node, lineView.gutter || lineView.text)
    } else {
      wrap.appendChild(node)
    }
    signalLater(widget, 'redraw')
  }
}

function positionLineWidget (widget, node, lineView, dims) {
  if (widget.noHScroll) {
    (lineView.alignable || (lineView.alignable = [])).push(node)
    var width = dims.wrapperWidth
    node.style.left = dims.fixedPos + 'px'
    if (!widget.coverGutter) {
      width -= dims.gutterTotalWidth
      node.style.paddingLeft = dims.gutterTotalWidth + 'px'
    }
    node.style.width = width + 'px'
  }
  if (widget.coverGutter) {
    node.style.zIndex = 5
    node.style.position = 'relative'
    if (!widget.noHScroll) {
      node.style.marginLeft = -dims.gutterTotalWidth + 'px'
    }
  }
}

function widgetHeight (widget) {
  if (widget.height != null) {
    return widget.height
  }
  var cm = widget.doc.cm
  if (!cm) {
    return 0
  }
  if (!contains(document.body, widget.node)) {
    var parentStyle = 'position: relative;'
    if (widget.coverGutter) {
      parentStyle += 'margin-left: -' + cm.display.gutters.offsetWidth + 'px;'
    }
    if (widget.noHScroll) {
      parentStyle += 'width: ' + cm.display.wrapper.clientWidth + 'px;'
    }
    removeChildrenAndAdd(cm.display.measure, elt('div', [widget.node], null, parentStyle))
  }
  return widget.height = widget.node.parentNode.offsetHeight
}

// Return true when the given mouse event happened in a widget
function eventInWidget (display, e) {
  for (var n = e_target(e); n != display.wrapper; n = n.parentNode) {
    if (!n || (n.nodeType == 1 && n.getAttribute('cm-ignore-events') == 'true') ||
            (n.parentNode == display.sizer && n != display.mover)) {
      return true
    }
  }
}

// POSITION MEASUREMENT

function paddingTop (display) {
  return display.lineSpace.offsetTop
}

function paddingVert (display) {
  return display.mover.offsetHeight - display.lineSpace.offsetHeight
}

function paddingH (display) {
  if (display.cachedPaddingH) {
    return display.cachedPaddingH
  }
  var e = removeChildrenAndAdd(display.measure, elt('pre', 'x', 'CodeMirror-line-like'))
  var style = window.getComputedStyle ? window.getComputedStyle(e) : e.currentStyle
  var data = { left: parseInt(style.paddingLeft), right: parseInt(style.paddingRight) }
  if (!isNaN(data.left) && !isNaN(data.right)) {
    display.cachedPaddingH = data
  }
  return data
}

function scrollGap (cm) {
  return scrollerGap - cm.display.nativeBarWidth
}

function displayWidth (cm) {
  return cm.display.scroller.clientWidth - scrollGap(cm) - cm.display.barWidth
}

function displayHeight (cm) {
  return cm.display.scroller.clientHeight - scrollGap(cm) - cm.display.barHeight
}

// Ensure the lineView.wrapping.heights array is populated. This is
// an array of bottom offsets for the lines that make up a drawn
// line. When lineWrapping is on, there might be more than one
// height.
function ensureLineHeights (cm, lineView, rect) {
  var wrapping = cm.options.lineWrapping
  var curWidth = wrapping && displayWidth(cm)
  if (!lineView.measure.heights || wrapping && lineView.measure.width != curWidth) {
    var heights = lineView.measure.heights = []
    if (wrapping) {
      lineView.measure.width = curWidth
      var rects = lineView.text.firstChild.getClientRects()
      for (var i = 0; i < rects.length - 1; i++) {
        var cur = rects[i]; var next = rects[i + 1]
        if (Math.abs(cur.bottom - next.bottom) > 2) {
          heights.push((cur.bottom + next.top) / 2 - rect.top)
        }
      }
    }
    heights.push(rect.bottom - rect.top)
  }
}

// Find a line map (mapping character offsets to text nodes) and a
// measurement cache for the given line number. (A line view might
// contain multiple lines when collapsed ranges are present.)
function mapFromLineView (lineView, line, lineN) {
  if (lineView.line == line) {
    return { map: lineView.measure.map, cache: lineView.measure.cache }
  }
  for (var i = 0; i < lineView.rest.length; i++) {
    if (lineView.rest[i] == line) {
      return { map: lineView.measure.maps[i], cache: lineView.measure.caches[i] }
    }
  }
  for (var i$1 = 0; i$1 < lineView.rest.length; i$1++) {
    if (lineNo(lineView.rest[i$1]) > lineN) {
      return { map: lineView.measure.maps[i$1], cache: lineView.measure.caches[i$1], before: true }
    }
  }
}

// Render a line into the hidden node display.externalMeasured. Used
// when measurement is needed for a line that's not in the viewport.
function updateExternalMeasurement (cm, line) {
  line = visualLine(line)
  var lineN = lineNo(line)
  var view = cm.display.externalMeasured = new LineView(cm.doc, line, lineN)
  view.lineN = lineN
  var built = view.built = buildLineContent(cm, view)
  view.text = built.pre
  removeChildrenAndAdd(cm.display.lineMeasure, built.pre)
  return view
}

// Get a {top, bottom, left, right} box (in line-local coordinates)
// for a given character.
function measureChar (cm, line, ch, bias) {
  return measureCharPrepared(cm, prepareMeasureForLine(cm, line), ch, bias)
}

// Find a line view that corresponds to the given line number.
function findViewForLine (cm, lineN) {
  if (lineN >= cm.display.viewFrom && lineN < cm.display.viewTo) {
    return cm.display.view[findViewIndex(cm, lineN)]
  }
  var ext = cm.display.externalMeasured
  if (ext && lineN >= ext.lineN && lineN < ext.lineN + ext.size) {
    return ext
  }
}

// Measurement can be split in two steps, the set-up work that
// applies to the whole line, and the measurement of the actual
// character. Functions like coordsChar, that need to do a lot of
// measurements in a row, can thus ensure that the set-up work is
// only done once.
function prepareMeasureForLine (cm, line) {
  var lineN = lineNo(line)
  var view = findViewForLine(cm, lineN)
  if (view && !view.text) {
    view = null
  } else if (view && view.changes) {
    updateLineForChanges(cm, view, lineN, getDimensions(cm))
    cm.curOp.forceUpdate = true
  }
  if (!view) {
    view = updateExternalMeasurement(cm, line)
  }

  var info = mapFromLineView(view, line, lineN)
  return {
    line: line,
    view: view,
    rect: null,
    map: info.map,
    cache: info.cache,
    before: info.before,
    hasHeights: false
  }
}

// Given a prepared measurement object, measures the position of an
// actual character (or fetches it from the cache).
function measureCharPrepared (cm, prepared, ch, bias, varHeight) {
  if (prepared.before) {
    ch = -1
  }
  var key = ch + (bias || ''); var found
  if (prepared.cache.hasOwnProperty(key)) {
    found = prepared.cache[key]
  } else {
    if (!prepared.rect) {
      prepared.rect = prepared.view.text.getBoundingClientRect()
    }
    if (!prepared.hasHeights) {
      ensureLineHeights(cm, prepared.view, prepared.rect)
      prepared.hasHeights = true
    }
    found = measureCharInner(cm, prepared, ch, bias)
    if (!found.bogus) {
      prepared.cache[key] = found
    }
  }
  return {
    left: found.left,
    right: found.right,
    top: varHeight ? found.rtop : found.top,
    bottom: varHeight ? found.rbottom : found.bottom
  }
}

var nullRect = { left: 0, right: 0, top: 0, bottom: 0 }

function nodeAndOffsetInLineMap (map$$1, ch, bias) {
  var node, start, end, collapse, mStart, mEnd
  // First, search the line map for the text node corresponding to,
  // or closest to, the target character.
  for (var i = 0; i < map$$1.length; i += 3) {
    mStart = map$$1[i]
    mEnd = map$$1[i + 1]
    if (ch < mStart) {
      start = 0
      end = 1
      collapse = 'left'
    } else if (ch < mEnd) {
      start = ch - mStart
      end = start + 1
    } else if (i == map$$1.length - 3 || ch == mEnd && map$$1[i + 3] > ch) {
      end = mEnd - mStart
      start = end - 1
      if (ch >= mEnd) {
        collapse = 'right'
      }
    }
    if (start != null) {
      node = map$$1[i + 2]
      if (mStart == mEnd && bias == (node.insertLeft ? 'left' : 'right')) {
        collapse = bias
      }
      if (bias == 'left' && start == 0) {
        while (i && map$$1[i - 2] == map$$1[i - 3] && map$$1[i - 1].insertLeft) {
          node = map$$1[(i -= 3) + 2]
          collapse = 'left'
        }
      }
      if (bias == 'right' && start == mEnd - mStart) {
        while (i < map$$1.length - 3 && map$$1[i + 3] == map$$1[i + 4] && !map$$1[i + 5].insertLeft) {
          node = map$$1[(i += 3) + 2]
          collapse = 'right'
        }
      }
      break
    }
  }
  return { node: node, start: start, end: end, collapse: collapse, coverStart: mStart, coverEnd: mEnd }
}

function getUsefulRect (rects, bias) {
  var rect = nullRect
  if (bias == 'left') {
    for (var i = 0; i < rects.length; i++) {
      if ((rect = rects[i]).left != rect.right) {
        break
      }
    }
  } else {
    for (var i$1 = rects.length - 1; i$1 >= 0; i$1--) {
      if ((rect = rects[i$1]).left != rect.right) {
        break
      }
    }
  }
  return rect
}

function measureCharInner (cm, prepared, ch, bias) {
  var place = nodeAndOffsetInLineMap(prepared.map, ch, bias)
  var node = place.node; var start = place.start; var end = place.end; var collapse = place.collapse

  var rect
  if (node.nodeType == 3) { // If it is a text node, use a range to retrieve the coordinates.
    for (var i$1 = 0; i$1 < 4; i$1++) { // Retry a maximum of 4 times when nonsense rectangles are returned
      while (start && isExtendingChar(prepared.line.text.charAt(place.coverStart + start))) {
        --start
      }
      while (place.coverStart + end < place.coverEnd && isExtendingChar(prepared.line.text.charAt(place.coverStart + end))) {
        ++end
      }
      if (ie && ie_version < 9 && start == 0 && end == place.coverEnd - place.coverStart) {
        rect = node.parentNode.getBoundingClientRect()
      } else {
        rect = getUsefulRect(range(node, start, end).getClientRects(), bias)
      }
      if (rect.left || rect.right || start == 0) {
        break
      }
      end = start
      start = start - 1
      collapse = 'right'
    }
    if (ie && ie_version < 11) {
      rect = maybeUpdateRectForZooming(cm.display.measure, rect)
    }
  } else { // If it is a widget, simply get the box for the whole widget.
    if (start > 0) {
      collapse = bias = 'right'
    }
    var rects
    if (cm.options.lineWrapping && (rects = node.getClientRects()).length > 1) {
      rect = rects[bias == 'right' ? rects.length - 1 : 0]
    } else {
      rect = node.getBoundingClientRect()
    }
  }
  if (ie && ie_version < 9 && !start && (!rect || !rect.left && !rect.right)) {
    var rSpan = node.parentNode.getClientRects()[0]
    if (rSpan) {
      rect = { left: rSpan.left, right: rSpan.left + charWidth(cm.display), top: rSpan.top, bottom: rSpan.bottom }
    } else {
      rect = nullRect
    }
  }

  var rtop = rect.top - prepared.rect.top; var rbot = rect.bottom - prepared.rect.top
  var mid = (rtop + rbot) / 2
  var heights = prepared.view.measure.heights
  var i = 0
  for (; i < heights.length - 1; i++) {
    if (mid < heights[i]) {
      break
    }
  }
  var top = i ? heights[i - 1] : 0; var bot = heights[i]
  var result = {
    left: (collapse == 'right' ? rect.right : rect.left) - prepared.rect.left,
    right: (collapse == 'left' ? rect.left : rect.right) - prepared.rect.left,
    top: top,
    bottom: bot
  }
  if (!rect.left && !rect.right) {
    result.bogus = true
  }
  if (!cm.options.singleCursorHeightPerLine) {
    result.rtop = rtop
    result.rbottom = rbot
  }

  return result
}

// Work around problem with bounding client rects on ranges being
// returned incorrectly when zoomed on IE10 and below.
function maybeUpdateRectForZooming (measure, rect) {
  if (!window.screen || screen.logicalXDPI == null ||
        screen.logicalXDPI == screen.deviceXDPI || !hasBadZoomedRects(measure)) {
    return rect
  }
  var scaleX = screen.logicalXDPI / screen.deviceXDPI
  var scaleY = screen.logicalYDPI / screen.deviceYDPI
  return {
    left: rect.left * scaleX,
    right: rect.right * scaleX,
    top: rect.top * scaleY,
    bottom: rect.bottom * scaleY
  }
}

function clearLineMeasurementCacheFor (lineView) {
  if (lineView.measure) {
    lineView.measure.cache = {}
    lineView.measure.heights = null
    if (lineView.rest) {
      for (var i = 0; i < lineView.rest.length; i++) {
        lineView.measure.caches[i] = {}
      }
    }
  }
}

function clearLineMeasurementCache (cm) {
  cm.display.externalMeasure = null
  removeChildren(cm.display.lineMeasure)
  for (var i = 0; i < cm.display.view.length; i++) {
    clearLineMeasurementCacheFor(cm.display.view[i])
  }
}

function clearCaches (cm) {
  clearLineMeasurementCache(cm)
  cm.display.cachedCharWidth = cm.display.cachedTextHeight = cm.display.cachedPaddingH = null
  if (!cm.options.lineWrapping) {
    cm.display.maxLineChanged = true
  }
  cm.display.lineNumChars = null
}

function pageScrollX () {
  // Work around https://bugs.chromium.org/p/chromium/issues/detail?id=489206
  // which causes page_Offset and bounding client rects to use
  // different reference viewports and invalidate our calculations.
  if (chrome && android) {
    return -(document.body.getBoundingClientRect().left - parseInt(getComputedStyle(document.body).marginLeft))
  }
  return window.pageXOffset || (document.documentElement || document.body).scrollLeft
}

function pageScrollY () {
  if (chrome && android) {
    return -(document.body.getBoundingClientRect().top - parseInt(getComputedStyle(document.body).marginTop))
  }
  return window.pageYOffset || (document.documentElement || document.body).scrollTop
}

function widgetTopHeight (lineObj) {
  var height = 0
  if (lineObj.widgets) {
    for (var i = 0; i < lineObj.widgets.length; ++i) {
      if (lineObj.widgets[i].above) {
        height += widgetHeight(lineObj.widgets[i])
      }
    }
  }
  return height
}

// Converts a {top, bottom, left, right} box from line-local
// coordinates into another coordinate system. Context may be one of
// "line", "div" (display.lineDiv), "local"./null (src), "window",
// or "page".
function intoCoordSystem (cm, lineObj, rect, context, includeWidgets) {
  if (!includeWidgets) {
    var height = widgetTopHeight(lineObj)
    rect.top += height
    rect.bottom += height
  }
  if (context == 'line') {
    return rect
  }
  if (!context) {
    context = 'local'
  }
  var yOff = heightAtLine(lineObj)
  if (context == 'local') {
    yOff += paddingTop(cm.display)
  } else {
    yOff -= cm.display.viewOffset
  }
  if (context == 'page' || context == 'window') {
    var lOff = cm.display.lineSpace.getBoundingClientRect()
    yOff += lOff.top + (context == 'window' ? 0 : pageScrollY())
    var xOff = lOff.left + (context == 'window' ? 0 : pageScrollX())
    rect.left += xOff
    rect.right += xOff
  }
  rect.top += yOff
  rect.bottom += yOff
  return rect
}

// Coverts a box from "div" coords to another coordinate system.
// Context may be "window", "page", "div", or "local"./null.
function fromCoordSystem (cm, coords, context) {
  if (context == 'div') {
    return coords
  }
  var left = coords.left; var top = coords.top
  // First move into "page" coordinate system
  if (context == 'page') {
    left -= pageScrollX()
    top -= pageScrollY()
  } else if (context == 'local' || !context) {
    var localBox = cm.display.sizer.getBoundingClientRect()
    left += localBox.left
    top += localBox.top
  }

  var lineSpaceBox = cm.display.lineSpace.getBoundingClientRect()
  return { left: left - lineSpaceBox.left, top: top - lineSpaceBox.top }
}

function charCoords (cm, pos, context, lineObj, bias) {
  if (!lineObj) {
    lineObj = getLine(cm.doc, pos.line)
  }
  return intoCoordSystem(cm, lineObj, measureChar(cm, lineObj, pos.ch, bias), context)
}

// Returns a box for a given cursor position, which may have an
// 'other' property containing the position of the secondary cursor
// on a bidi boundary.
// A cursor Pos(line, char, "before") is on the same visual line as `char - 1`
// and after `char - 1` in writing order of `char - 1`
// A cursor Pos(line, char, "after") is on the same visual line as `char`
// and before `char` in writing order of `char`
// Examples (upper-case letters are RTL, lower-case are LTR):
//     Pos(0, 1, ...)
//     before   after
// ab     a|b     a|b
// aB     a|B     aB|
// Ab     |Ab     A|b
// AB     B|A     B|A
// Every position after the last character on a line is considered to stick
// to the last character on the line.
function cursorCoords (cm, pos, context, lineObj, preparedMeasure, varHeight) {
  lineObj = lineObj || getLine(cm.doc, pos.line)
  if (!preparedMeasure) {
    preparedMeasure = prepareMeasureForLine(cm, lineObj)
  }

  function get (ch, right) {
    var m = measureCharPrepared(cm, preparedMeasure, ch, right ? 'right' : 'left', varHeight)
    if (right) {
      m.left = m.right
    } else {
      m.right = m.left
    }
    return intoCoordSystem(cm, lineObj, m, context)
  }

  var order = getOrder(lineObj, cm.doc.direction); var ch = pos.ch; var sticky = pos.sticky
  if (ch >= lineObj.text.length) {
    ch = lineObj.text.length
    sticky = 'before'
  } else if (ch <= 0) {
    ch = 0
    sticky = 'after'
  }
  if (!order) {
    return get(sticky == 'before' ? ch - 1 : ch, sticky == 'before')
  }

  function getBidi (ch, partPos, invert) {
    var part = order[partPos]; var right = part.level == 1
    return get(invert ? ch - 1 : ch, right != invert)
  }

  var partPos = getBidiPartAt(order, ch, sticky)
  var other = bidiOther
  var val = getBidi(ch, partPos, sticky == 'before')
  if (other != null) {
    val.other = getBidi(ch, other, sticky != 'before')
  }
  return val
}

// Used to cheaply estimate the coordinates for a position. Used for
// intermediate scroll updates.
function estimateCoords (cm, pos) {
  var left = 0
  pos = clipPos(cm.doc, pos)
  if (!cm.options.lineWrapping) {
    left = charWidth(cm.display) * pos.ch
  }
  var lineObj = getLine(cm.doc, pos.line)
  var top = heightAtLine(lineObj) + paddingTop(cm.display)
  return { left: left, right: left, top: top, bottom: top + lineObj.height }
}

// Positions returned by coordsChar contain some extra information.
// xRel is the relative x position of the input coordinates compared
// to the found position (so xRel > 0 means the coordinates are to
// the right of the character position, for example). When outside
// is true, that means the coordinates lie outside the line's
// vertical range.
function PosWithInfo (line, ch, sticky, outside, xRel) {
  var pos = Pos(line, ch, sticky)
  pos.xRel = xRel
  if (outside) {
    pos.outside = outside
  }
  return pos
}

// Compute the character position closest to the given coordinates.
// Input must be lineSpace-local ("div" coordinate system).
function coordsChar (cm, x, y) {
  var doc = cm.doc
  y += cm.display.viewOffset
  if (y < 0) {
    return PosWithInfo(doc.first, 0, null, -1, -1)
  }
  var lineN = lineAtHeight(doc, y); var last = doc.first + doc.size - 1
  if (lineN > last) {
    return PosWithInfo(doc.first + doc.size - 1, getLine(doc, last).text.length, null, 1, 1)
  }
  if (x < 0) {
    x = 0
  }

  var lineObj = getLine(doc, lineN)
  for (; ;) {
    var found = coordsCharInner(cm, lineObj, lineN, x, y)
    var collapsed = collapsedSpanAround(lineObj, found.ch + (found.xRel > 0 || found.outside > 0 ? 1 : 0))
    if (!collapsed) {
      return found
    }
    var rangeEnd = collapsed.find(1)
    if (rangeEnd.line == lineN) {
      return rangeEnd
    }
    lineObj = getLine(doc, lineN = rangeEnd.line)
  }
}

function wrappedLineExtent (cm, lineObj, preparedMeasure, y) {
  y -= widgetTopHeight(lineObj)
  var end = lineObj.text.length
  var begin = findFirst(function (ch) {
    return measureCharPrepared(cm, preparedMeasure, ch - 1).bottom <= y
  }, end, 0)
  end = findFirst(function (ch) {
    return measureCharPrepared(cm, preparedMeasure, ch).top > y
  }, begin, end)
  return { begin: begin, end: end }
}

function wrappedLineExtentChar (cm, lineObj, preparedMeasure, target) {
  if (!preparedMeasure) {
    preparedMeasure = prepareMeasureForLine(cm, lineObj)
  }
  var targetTop = intoCoordSystem(cm, lineObj, measureCharPrepared(cm, preparedMeasure, target), 'line').top
  return wrappedLineExtent(cm, lineObj, preparedMeasure, targetTop)
}

// Returns true if the given side of a box is after the given
// coordinates, in top-to-bottom, left-to-right order.
function boxIsAfter (box, x, y, left) {
  return box.bottom <= y ? false : box.top > y ? true : (left ? box.left : box.right) > x
}

function coordsCharInner (cm, lineObj, lineNo$$1, x, y) {
  // Move y into line-local coordinate space
  y -= heightAtLine(lineObj)
  var preparedMeasure = prepareMeasureForLine(cm, lineObj)
  // When directly calling `measureCharPrepared`, we have to adjust
  // for the widgets at this line.
  var widgetHeight$$1 = widgetTopHeight(lineObj)
  var begin = 0; var end = lineObj.text.length; var ltr = true

  var order = getOrder(lineObj, cm.doc.direction)
  // If the line isn't plain left-to-right text, first figure out
  // which bidi section the coordinates fall into.
  if (order) {
    var part = (cm.options.lineWrapping ? coordsBidiPartWrapped : coordsBidiPart)
    (cm, lineObj, lineNo$$1, preparedMeasure, order, x, y)
    ltr = part.level != 1
    // The awkward -1 offsets are needed because findFirst (called
    // on these below) will treat its first bound as inclusive,
    // second as exclusive, but we want to actually address the
    // characters in the part's range
    begin = ltr ? part.from : part.to - 1
    end = ltr ? part.to : part.from - 1
  }

  // A binary search to find the first character whose bounding box
  // starts after the coordinates. If we run across any whose box wrap
  // the coordinates, store that.
  var chAround = null; var boxAround = null
  var ch = findFirst(function (ch) {
    var box = measureCharPrepared(cm, preparedMeasure, ch)
    box.top += widgetHeight$$1
    box.bottom += widgetHeight$$1
    if (!boxIsAfter(box, x, y, false)) {
      return false
    }
    if (box.top <= y && box.left <= x) {
      chAround = ch
      boxAround = box
    }
    return true
  }, begin, end)

  var baseX; var sticky; var outside = false
  // If a box around the coordinates was found, use that
  if (boxAround) {
    // Distinguish coordinates nearer to the left or right side of the box
    var atLeft = x - boxAround.left < boxAround.right - x; var atStart = atLeft == ltr
    ch = chAround + (atStart ? 0 : 1)
    sticky = atStart ? 'after' : 'before'
    baseX = atLeft ? boxAround.left : boxAround.right
  } else {
    // (Adjust for extended bound, if necessary.)
    if (!ltr && (ch == end || ch == begin)) {
      ch++
    }
    // To determine which side to associate with, get the box to the
    // left of the character and compare it's vertical position to the
    // coordinates
    sticky = ch == 0 ? 'after' : ch == lineObj.text.length ? 'before'
      : (measureCharPrepared(cm, preparedMeasure, ch - (ltr ? 1 : 0)).bottom + widgetHeight$$1 <= y) == ltr
        ? 'after' : 'before'
    // Now get accurate coordinates for this place, in order to get a
    // base X position
    var coords = cursorCoords(cm, Pos(lineNo$$1, ch, sticky), 'line', lineObj, preparedMeasure)
    baseX = coords.left
    outside = y < coords.top ? -1 : y >= coords.bottom ? 1 : 0
  }

  ch = skipExtendingChars(lineObj.text, ch, 1)
  return PosWithInfo(lineNo$$1, ch, sticky, outside, x - baseX)
}

function coordsBidiPart (cm, lineObj, lineNo$$1, preparedMeasure, order, x, y) {
  // Bidi parts are sorted left-to-right, and in a non-line-wrapping
  // situation, we can take this ordering to correspond to the visual
  // ordering. This finds the first part whose end is after the given
  // coordinates.
  var index = findFirst(function (i) {
    var part = order[i]; var ltr = part.level != 1
    return boxIsAfter(cursorCoords(cm, Pos(lineNo$$1, ltr ? part.to : part.from, ltr ? 'before' : 'after'),
      'line', lineObj, preparedMeasure), x, y, true)
  }, 0, order.length - 1)
  var part = order[index]
  // If this isn't the first part, the part's start is also after
  // the coordinates, and the coordinates aren't on the same line as
  // that start, move one part back.
  if (index > 0) {
    var ltr = part.level != 1
    var start = cursorCoords(cm, Pos(lineNo$$1, ltr ? part.from : part.to, ltr ? 'after' : 'before'),
      'line', lineObj, preparedMeasure)
    if (boxIsAfter(start, x, y, true) && start.top > y) {
      part = order[index - 1]
    }
  }
  return part
}

function coordsBidiPartWrapped (cm, lineObj, _lineNo, preparedMeasure, order, x, y) {
  // In a wrapped line, rtl text on wrapping boundaries can do things
  // that don't correspond to the ordering in our `order` array at
  // all, so a binary search doesn't work, and we want to return a
  // part that only spans one line so that the binary search in
  // coordsCharInner is safe. As such, we first find the extent of the
  // wrapped line, and then do a flat search in which we discard any
  // spans that aren't on the line.
  var ref = wrappedLineExtent(cm, lineObj, preparedMeasure, y)
  var begin = ref.begin
  var end = ref.end
  if (/\s/.test(lineObj.text.charAt(end - 1))) {
    end--
  }
  var part = null; var closestDist = null
  for (var i = 0; i < order.length; i++) {
    var p = order[i]
    if (p.from >= end || p.to <= begin) {
      continue
    }
    var ltr = p.level != 1
    var endX = measureCharPrepared(cm, preparedMeasure, ltr ? Math.min(end, p.to) - 1 : Math.max(begin, p.from)).right
    // Weigh against spans ending before this, so that they are only
    // picked if nothing ends after
    var dist = endX < x ? x - endX + 1e9 : endX - x
    if (!part || closestDist > dist) {
      part = p
      closestDist = dist
    }
  }
  if (!part) {
    part = order[order.length - 1]
  }
  // Clip the part to the wrapped line.
  if (part.from < begin) {
    part = { from: begin, to: part.to, level: part.level }
  }
  if (part.to > end) {
    part = { from: part.from, to: end, level: part.level }
  }
  return part
}

var measureText

// Compute the default text height.
function textHeight (display) {
  if (display.cachedTextHeight != null) {
    return display.cachedTextHeight
  }
  if (measureText == null) {
    measureText = elt('pre', null, 'CodeMirror-line-like')
    // Measure a bunch of lines, for browsers that compute
    // fractional heights.
    for (var i = 0; i < 49; ++i) {
      measureText.appendChild(document.createTextNode('x'))
      measureText.appendChild(elt('br'))
    }
    measureText.appendChild(document.createTextNode('x'))
  }
  removeChildrenAndAdd(display.measure, measureText)
  var height = measureText.offsetHeight / 50
  if (height > 3) {
    display.cachedTextHeight = height
  }
  removeChildren(display.measure)
  return height || 1
}

// Compute the default character width.
function charWidth (display) {
  if (display.cachedCharWidth != null) {
    return display.cachedCharWidth
  }
  var anchor = elt('span', 'xxxxxxxxxx')
  var pre = elt('pre', [anchor], 'CodeMirror-line-like')
  removeChildrenAndAdd(display.measure, pre)
  var rect = anchor.getBoundingClientRect(); var width = (rect.right - rect.left) / 10
  if (width > 2) {
    display.cachedCharWidth = width
  }
  return width || 10
}

// Do a bulk-read of the DOM positions and sizes needed to draw the
// view, so that we don't interleave reading and writing to the DOM.
function getDimensions (cm) {
  var d = cm.display; var left = {}; var width = {}
  var gutterLeft = d.gutters.clientLeft
  for (var n = d.gutters.firstChild, i = 0; n; n = n.nextSibling, ++i) {
    var id = cm.display.gutterSpecs[i].className
    left[id] = n.offsetLeft + n.clientLeft + gutterLeft
    width[id] = n.clientWidth
  }
  return {
    fixedPos: compensateForHScroll(d),
    gutterTotalWidth: d.gutters.offsetWidth,
    gutterLeft: left,
    gutterWidth: width,
    wrapperWidth: d.wrapper.clientWidth
  }
}

// Computes display.scroller.scrollLeft + display.gutters.offsetWidth,
// but using getBoundingClientRect to get a sub-pixel-accurate
// result.
function compensateForHScroll (display) {
  return display.scroller.getBoundingClientRect().left - display.sizer.getBoundingClientRect().left
}

// Returns a function that estimates the height of a line, to use as
// first approximation until the line becomes visible (and is thus
// properly measurable).
function estimateHeight (cm) {
  var th = textHeight(cm.display); var wrapping = cm.options.lineWrapping
  var perLine = wrapping && Math.max(5, cm.display.scroller.clientWidth / charWidth(cm.display) - 3)
  return function (line) {
    if (lineIsHidden(cm.doc, line)) {
      return 0
    }

    var widgetsHeight = 0
    if (line.widgets) {
      for (var i = 0; i < line.widgets.length; i++) {
        if (line.widgets[i].height) {
          widgetsHeight += line.widgets[i].height
        }
      }
    }

    if (wrapping) {
      return widgetsHeight + (Math.ceil(line.text.length / perLine) || 1) * th
    } else {
      return widgetsHeight + th
    }
  }
}

function estimateLineHeights (cm) {
  var doc = cm.doc; var est = estimateHeight(cm)
  doc.iter(function (line) {
    var estHeight = est(line)
    if (estHeight != line.height) {
      updateLineHeight(line, estHeight)
    }
  })
}

// Given a mouse event, find the corresponding position. If liberal
// is false, it checks whether a gutter or scrollbar was clicked,
// and returns null if it was. forRect is used by rectangular
// selections, and tries to estimate a character position even for
// coordinates beyond the right of the text.
function posFromMouse (cm, e, liberal, forRect) {
  var display = cm.display
  if (!liberal && e_target(e).getAttribute('cm-not-content') == 'true') {
    return null
  }

  var x; var y; var space = display.lineSpace.getBoundingClientRect()
  // Fails unpredictably on IE[67] when mouse is dragged around quickly.
  try {
    x = e.clientX - space.left
    y = e.clientY - space.top
  } catch (e) {
    return null
  }
  var coords = coordsChar(cm, x, y); var line
  if (forRect && coords.xRel == 1 && (line = getLine(cm.doc, coords.line).text).length == coords.ch) {
    var colDiff = countColumn(line, line.length, cm.options.tabSize) - line.length
    coords = Pos(coords.line, Math.max(0, Math.round((x - paddingH(cm.display).left) / charWidth(cm.display)) - colDiff))
  }
  return coords
}

// Find the view element corresponding to a given line. Return null
// when the line isn't visible.
function findViewIndex (cm, n) {
  if (n >= cm.display.viewTo) {
    return null
  }
  n -= cm.display.viewFrom
  if (n < 0) {
    return null
  }
  var view = cm.display.view
  for (var i = 0; i < view.length; i++) {
    n -= view[i].size
    if (n < 0) {
      return i
    }
  }
}

// Updates the display.view data structure for a given change to the
// document. From and to are in pre-change coordinates. Lendiff is
// the amount of lines added or subtracted by the change. This is
// used for changes that span multiple lines, or change the way
// lines are divided into visual lines. regLineChange (below)
// registers single-line changes.
function regChange (cm, from, to, lendiff) {
  if (from == null) {
    from = cm.doc.first
  }
  if (to == null) {
    to = cm.doc.first + cm.doc.size
  }
  if (!lendiff) {
    lendiff = 0
  }

  var display = cm.display
  if (lendiff && to < display.viewTo &&
        (display.updateLineNumbers == null || display.updateLineNumbers > from)) {
    display.updateLineNumbers = from
  }

  cm.curOp.viewChanged = true

  if (from >= display.viewTo) { // Change after
    if (sawCollapsedSpans && visualLineNo(cm.doc, from) < display.viewTo) {
      resetView(cm)
    }
  } else if (to <= display.viewFrom) { // Change before
    if (sawCollapsedSpans && visualLineEndNo(cm.doc, to + lendiff) > display.viewFrom) {
      resetView(cm)
    } else {
      display.viewFrom += lendiff
      display.viewTo += lendiff
    }
  } else if (from <= display.viewFrom && to >= display.viewTo) { // Full overlap
    resetView(cm)
  } else if (from <= display.viewFrom) { // Top overlap
    var cut = viewCuttingPoint(cm, to, to + lendiff, 1)
    if (cut) {
      display.view = display.view.slice(cut.index)
      display.viewFrom = cut.lineN
      display.viewTo += lendiff
    } else {
      resetView(cm)
    }
  } else if (to >= display.viewTo) { // Bottom overlap
    var cut$1 = viewCuttingPoint(cm, from, from, -1)
    if (cut$1) {
      display.view = display.view.slice(0, cut$1.index)
      display.viewTo = cut$1.lineN
    } else {
      resetView(cm)
    }
  } else { // Gap in the middle
    var cutTop = viewCuttingPoint(cm, from, from, -1)
    var cutBot = viewCuttingPoint(cm, to, to + lendiff, 1)
    if (cutTop && cutBot) {
      display.view = display.view.slice(0, cutTop.index)
        .concat(buildViewArray(cm, cutTop.lineN, cutBot.lineN))
        .concat(display.view.slice(cutBot.index))
      display.viewTo += lendiff
    } else {
      resetView(cm)
    }
  }

  var ext = display.externalMeasured
  if (ext) {
    if (to < ext.lineN) {
      ext.lineN += lendiff
    } else if (from < ext.lineN + ext.size) {
      display.externalMeasured = null
    }
  }
}

// Register a change to a single line. Type must be one of "text",
// "gutter", "class", "widget"
function regLineChange (cm, line, type) {
  cm.curOp.viewChanged = true
  var display = cm.display; var ext = cm.display.externalMeasured
  if (ext && line >= ext.lineN && line < ext.lineN + ext.size) {
    display.externalMeasured = null
  }

  if (line < display.viewFrom || line >= display.viewTo) {
    return
  }
  var lineView = display.view[findViewIndex(cm, line)]
  if (lineView.node == null) {
    return
  }
  var arr = lineView.changes || (lineView.changes = [])
  if (indexOf(arr, type) == -1) {
    arr.push(type)
  }
}

// Clear the view.
function resetView (cm) {
  cm.display.viewFrom = cm.display.viewTo = cm.doc.first
  cm.display.view = []
  cm.display.viewOffset = 0
}

function viewCuttingPoint (cm, oldN, newN, dir) {
  var index = findViewIndex(cm, oldN); var diff; var view = cm.display.view
  if (!sawCollapsedSpans || newN == cm.doc.first + cm.doc.size) {
    return { index: index, lineN: newN }
  }
  var n = cm.display.viewFrom
  for (var i = 0; i < index; i++) {
    n += view[i].size
  }
  if (n != oldN) {
    if (dir > 0) {
      if (index == view.length - 1) {
        return null
      }
      diff = (n + view[index].size) - oldN
      index++
    } else {
      diff = n - oldN
    }
    oldN += diff
    newN += diff
  }
  while (visualLineNo(cm.doc, newN) != newN) {
    if (index == (dir < 0 ? 0 : view.length - 1)) {
      return null
    }
    newN += dir * view[index - (dir < 0 ? 1 : 0)].size
    index += dir
  }
  return { index: index, lineN: newN }
}

// Force the view to cover a given range, adding empty view element
// or clipping off existing ones as needed.
function adjustView (cm, from, to) {
  var display = cm.display; var view = display.view
  if (view.length == 0 || from >= display.viewTo || to <= display.viewFrom) {
    display.view = buildViewArray(cm, from, to)
    display.viewFrom = from
  } else {
    if (display.viewFrom > from) {
      display.view = buildViewArray(cm, from, display.viewFrom).concat(display.view)
    } else if (display.viewFrom < from) {
      display.view = display.view.slice(findViewIndex(cm, from))
    }
    display.viewFrom = from
    if (display.viewTo < to) {
      display.view = display.view.concat(buildViewArray(cm, display.viewTo, to))
    } else if (display.viewTo > to) {
      display.view = display.view.slice(0, findViewIndex(cm, to))
    }
  }
  display.viewTo = to
}

// Count the number of lines in the view whose DOM representation is
// out of date (or nonexistent).
function countDirtyView (cm) {
  var view = cm.display.view; var dirty = 0
  for (var i = 0; i < view.length; i++) {
    var lineView = view[i]
    if (!lineView.hidden && (!lineView.node || lineView.changes)) {
      ++dirty
    }
  }
  return dirty
}

function updateSelection (cm) {
  cm.display.input.showSelection(cm.display.input.prepareSelection())
}

function prepareSelection (cm, primary) {
  if (primary === void 0) primary = true

  var doc = cm.doc; var result = {}
  var curFragment = result.cursors = document.createDocumentFragment()
  var selFragment = result.selection = document.createDocumentFragment()

  for (var i = 0; i < doc.sel.ranges.length; i++) {
    if (!primary && i == doc.sel.primIndex) {
      continue
    }
    var range$$1 = doc.sel.ranges[i]
    if (range$$1.from().line >= cm.display.viewTo || range$$1.to().line < cm.display.viewFrom) {
      continue
    }
    var collapsed = range$$1.empty()
    if (collapsed || cm.options.showCursorWhenSelecting) {
      drawSelectionCursor(cm, range$$1.head, curFragment)
    }
    if (!collapsed) {
      drawSelectionRange(cm, range$$1, selFragment)
    }
  }
  return result
}

// Draws a cursor for the given range
function drawSelectionCursor (cm, head, output) {
  var pos = cursorCoords(cm, head, 'div', null, null, !cm.options.singleCursorHeightPerLine)

  var cursor = output.appendChild(elt('div', '\u00a0', 'CodeMirror-cursor'))
  cursor.style.left = pos.left + 'px'
  cursor.style.top = pos.top + 'px'
  cursor.style.height = Math.max(0, pos.bottom - pos.top) * cm.options.cursorHeight + 'px'

  if (pos.other) {
    // Secondary cursor, shown when on a 'jump' in bi-directional text
    var otherCursor = output.appendChild(elt('div', '\u00a0', 'CodeMirror-cursor CodeMirror-secondarycursor'))
    otherCursor.style.display = ''
    otherCursor.style.left = pos.other.left + 'px'
    otherCursor.style.top = pos.other.top + 'px'
    otherCursor.style.height = (pos.other.bottom - pos.other.top) * 0.85 + 'px'
  }
}

function cmpCoords (a, b) {
  return a.top - b.top || a.left - b.left
}

// Draws the given range as a highlighted selection
function drawSelectionRange (cm, range$$1, output) {
  var display = cm.display; var doc = cm.doc
  var fragment = document.createDocumentFragment()
  var padding = paddingH(cm.display); var leftSide = padding.left
  var rightSide = Math.max(display.sizerWidth, displayWidth(cm) - display.sizer.offsetLeft) - padding.right
  var docLTR = doc.direction == 'ltr'

  function add (left, top, width, bottom) {
    if (top < 0) {
      top = 0
    }
    top = Math.round(top)
    bottom = Math.round(bottom)
    fragment.appendChild(elt('div', null, 'CodeMirror-selected', ('position: absolute; left: ' + left + 'px;\n                             top: ' + top + 'px; width: ' + (width == null ? rightSide - left : width) + 'px;\n                             height: ' + (bottom - top) + 'px')))
  }

  function drawForLine (line, fromArg, toArg) {
    var lineObj = getLine(doc, line)
    var lineLen = lineObj.text.length
    var start, end

    function coords (ch, bias) {
      return charCoords(cm, Pos(line, ch), 'div', lineObj, bias)
    }

    function wrapX (pos, dir, side) {
      var extent = wrappedLineExtentChar(cm, lineObj, null, pos)
      var prop = (dir == 'ltr') == (side == 'after') ? 'left' : 'right'
      var ch = side == 'after' ? extent.begin : extent.end - (/\s/.test(lineObj.text.charAt(extent.end - 1)) ? 2 : 1)
      return coords(ch, prop)[prop]
    }

    var order = getOrder(lineObj, doc.direction)
    iterateBidiSections(order, fromArg || 0, toArg == null ? lineLen : toArg, function (from, to, dir, i) {
      var ltr = dir == 'ltr'
      var fromPos = coords(from, ltr ? 'left' : 'right')
      var toPos = coords(to - 1, ltr ? 'right' : 'left')

      var openStart = fromArg == null && from == 0; var openEnd = toArg == null && to == lineLen
      var first = i == 0; var last = !order || i == order.length - 1
      if (toPos.top - fromPos.top <= 3) { // Single line
        var openLeft = (docLTR ? openStart : openEnd) && first
        var openRight = (docLTR ? openEnd : openStart) && last
        var left = openLeft ? leftSide : (ltr ? fromPos : toPos).left
        var right = openRight ? rightSide : (ltr ? toPos : fromPos).right
        add(left, fromPos.top, right - left, fromPos.bottom)
      } else { // Multiple lines
        var topLeft, topRight, botLeft, botRight
        if (ltr) {
          topLeft = docLTR && openStart && first ? leftSide : fromPos.left
          topRight = docLTR ? rightSide : wrapX(from, dir, 'before')
          botLeft = docLTR ? leftSide : wrapX(to, dir, 'after')
          botRight = docLTR && openEnd && last ? rightSide : toPos.right
        } else {
          topLeft = !docLTR ? leftSide : wrapX(from, dir, 'before')
          topRight = !docLTR && openStart && first ? rightSide : fromPos.right
          botLeft = !docLTR && openEnd && last ? leftSide : toPos.left
          botRight = !docLTR ? rightSide : wrapX(to, dir, 'after')
        }
        add(topLeft, fromPos.top, topRight - topLeft, fromPos.bottom)
        if (fromPos.bottom < toPos.top) {
          add(leftSide, fromPos.bottom, null, toPos.top)
        }
        add(botLeft, toPos.top, botRight - botLeft, toPos.bottom)
      }

      if (!start || cmpCoords(fromPos, start) < 0) {
        start = fromPos
      }
      if (cmpCoords(toPos, start) < 0) {
        start = toPos
      }
      if (!end || cmpCoords(fromPos, end) < 0) {
        end = fromPos
      }
      if (cmpCoords(toPos, end) < 0) {
        end = toPos
      }
    })
    return { start: start, end: end }
  }

  var sFrom = range$$1.from(); var sTo = range$$1.to()
  if (sFrom.line == sTo.line) {
    drawForLine(sFrom.line, sFrom.ch, sTo.ch)
  } else {
    var fromLine = getLine(doc, sFrom.line); var toLine = getLine(doc, sTo.line)
    var singleVLine = visualLine(fromLine) == visualLine(toLine)
    var leftEnd = drawForLine(sFrom.line, sFrom.ch, singleVLine ? fromLine.text.length + 1 : null).end
    var rightStart = drawForLine(sTo.line, singleVLine ? 0 : null, sTo.ch).start
    if (singleVLine) {
      if (leftEnd.top < rightStart.top - 2) {
        add(leftEnd.right, leftEnd.top, null, leftEnd.bottom)
        add(leftSide, rightStart.top, rightStart.left, rightStart.bottom)
      } else {
        add(leftEnd.right, leftEnd.top, rightStart.left - leftEnd.right, leftEnd.bottom)
      }
    }
    if (leftEnd.bottom < rightStart.top) {
      add(leftSide, leftEnd.bottom, null, rightStart.top)
    }
  }

  output.appendChild(fragment)
}

// Cursor-blinking
function restartBlink (cm) {
  if (!cm.state.focused) {
    return
  }
  var display = cm.display
  clearInterval(display.blinker)
  var on = true
  display.cursorDiv.style.visibility = ''
  if (cm.options.cursorBlinkRate > 0) {
    display.blinker = setInterval(function () {
      return display.cursorDiv.style.visibility = (on = !on) ? '' : 'hidden'
    },
    cm.options.cursorBlinkRate)
  } else if (cm.options.cursorBlinkRate < 0) {
    display.cursorDiv.style.visibility = 'hidden'
  }
}

function ensureFocus (cm) {
  if (!cm.state.focused) {
    cm.display.input.focus()
    onFocus(cm)
  }
}

function delayBlurEvent (cm) {
  cm.state.delayingBlurEvent = true
  setTimeout(function () {
    if (cm.state.delayingBlurEvent) {
      cm.state.delayingBlurEvent = false
      onBlur(cm)
    }
  }, 100)
}

function onFocus (cm, e) {
  if (cm.state.delayingBlurEvent) {
    cm.state.delayingBlurEvent = false
  }

  if (cm.options.readOnly == 'nocursor') {
    return
  }
  if (!cm.state.focused) {
    signal(cm, 'focus', cm, e)
    cm.state.focused = true
    addClass(cm.display.wrapper, 'CodeMirror-focused')
    // This test prevents this from firing when a context
    // menu is closed (since the input reset would kill the
    // select-all detection hack)
    if (!cm.curOp && cm.display.selForContextMenu != cm.doc.sel) {
      cm.display.input.reset()
      if (webkit) {
        setTimeout(function () {
          return cm.display.input.reset(true)
        }, 20)
      } // Issue #1730
    }
    cm.display.input.receivedFocus()
  }
  restartBlink(cm)
}

function onBlur (cm, e) {
  if (cm.state.delayingBlurEvent) {
    return
  }

  if (cm.state.focused) {
    signal(cm, 'blur', cm, e)
    cm.state.focused = false
    rmClass(cm.display.wrapper, 'CodeMirror-focused')
  }
  clearInterval(cm.display.blinker)
  setTimeout(function () {
    if (!cm.state.focused) {
      cm.display.shift = false
    }
  }, 150)
}

// Read the actual heights of the rendered lines, and update their
// stored heights to match.
function updateHeightsInViewport (cm) {
  var display = cm.display
  var prevBottom = display.lineDiv.offsetTop
  for (var i = 0; i < display.view.length; i++) {
    var cur = display.view[i]; var wrapping = cm.options.lineWrapping
    var height = (void 0); var width = 0
    if (cur.hidden) {
      continue
    }
    if (ie && ie_version < 8) {
      var bot = cur.node.offsetTop + cur.node.offsetHeight
      height = bot - prevBottom
      prevBottom = bot
    } else {
      var box = cur.node.getBoundingClientRect()
      height = box.bottom - box.top
      // Check that lines don't extend past the right of the current
      // src width
      if (!wrapping && cur.text.firstChild) {
        width = cur.text.firstChild.getBoundingClientRect().right - box.left - 1
      }
    }
    var diff = cur.line.height - height
    if (diff > 0.005 || diff < -0.005) {
      updateLineHeight(cur.line, height)
      updateWidgetHeight(cur.line)
      if (cur.rest) {
        for (var j = 0; j < cur.rest.length; j++) {
          updateWidgetHeight(cur.rest[j])
        }
      }
    }
    if (width > cm.display.sizerWidth) {
      var chWidth = Math.ceil(width / charWidth(cm.display))
      if (chWidth > cm.display.maxLineLength) {
        cm.display.maxLineLength = chWidth
        cm.display.maxLine = cur.line
        cm.display.maxLineChanged = true
      }
    }
  }
}

// Read and store the height of line widgets associated with the
// given line.
function updateWidgetHeight (line) {
  if (line.widgets) {
    for (var i = 0; i < line.widgets.length; ++i) {
      var w = line.widgets[i]; var parent = w.node.parentNode
      if (parent) {
        w.height = parent.offsetHeight
      }
    }
  }
}

// Compute the lines that are visible in a given viewport (defaults
// the the current scroll position). viewport may contain top,
// height, and ensure (see op.scrollToPos) properties.
function visibleLines (display, doc, viewport) {
  var top = viewport && viewport.top != null ? Math.max(0, viewport.top) : display.scroller.scrollTop
  top = Math.floor(top - paddingTop(display))
  var bottom = viewport && viewport.bottom != null ? viewport.bottom : top + display.wrapper.clientHeight

  var from = lineAtHeight(doc, top); var to = lineAtHeight(doc, bottom)
  // Ensure is a {from: {line, ch}, to: {line, ch}} object, and
  // forces those lines into the viewport (if possible).
  if (viewport && viewport.ensure) {
    var ensureFrom = viewport.ensure.from.line; var ensureTo = viewport.ensure.to.line
    if (ensureFrom < from) {
      from = ensureFrom
      to = lineAtHeight(doc, heightAtLine(getLine(doc, ensureFrom)) + display.wrapper.clientHeight)
    } else if (Math.min(ensureTo, doc.lastLine()) >= to) {
      from = lineAtHeight(doc, heightAtLine(getLine(doc, ensureTo)) - display.wrapper.clientHeight)
      to = ensureTo
    }
  }
  return { from: from, to: Math.max(to, from + 1) }
}

// SCROLLING THINGS INTO VIEW

// If an src sits on the top or bottom of the window, partially
// scrolled out of view, this ensures that the cursor is visible.
function maybeScrollWindow (cm, rect) {
  if (signalDOMEvent(cm, 'scrollCursorIntoView')) {
    return
  }

  var display = cm.display; var box = display.sizer.getBoundingClientRect(); var doScroll = null
  if (rect.top + box.top < 0) {
    doScroll = true
  } else if (rect.bottom + box.top > (window.innerHeight || document.documentElement.clientHeight)) {
    doScroll = false
  }
  if (doScroll != null && !phantom) {
    var scrollNode = elt('div', '\u200b', null, ('position: absolute;\n                         top: ' + (rect.top - display.viewOffset - paddingTop(cm.display)) + 'px;\n                         height: ' + (rect.bottom - rect.top + scrollGap(cm) + display.barHeight) + 'px;\n                         left: ' + (rect.left) + 'px; width: ' + (Math.max(2, rect.right - rect.left)) + 'px;'))
    cm.display.lineSpace.appendChild(scrollNode)
    scrollNode.scrollIntoView(doScroll)
    cm.display.lineSpace.removeChild(scrollNode)
  }
}

// Scroll a given position into view (immediately), verifying that
// it actually became visible (as line heights are accurately
// measured, the position of something may 'drift' during drawing).
function scrollPosIntoView (cm, pos, end, margin) {
  if (margin == null) {
    margin = 0
  }
  var rect
  if (!cm.options.lineWrapping && pos == end) {
    // Set pos and end to the cursor positions around the character pos sticks to
    // If pos.sticky == "before", that is around pos.ch - 1, otherwise around pos.ch
    // If pos == Pos(_, 0, "before"), pos and end are unchanged
    pos = pos.ch ? Pos(pos.line, pos.sticky == 'before' ? pos.ch - 1 : pos.ch, 'after') : pos
    end = pos.sticky == 'before' ? Pos(pos.line, pos.ch + 1, 'before') : pos
  }
  for (var limit = 0; limit < 5; limit++) {
    var changed = false
    var coords = cursorCoords(cm, pos)
    var endCoords = !end || end == pos ? coords : cursorCoords(cm, end)
    rect = {
      left: Math.min(coords.left, endCoords.left),
      top: Math.min(coords.top, endCoords.top) - margin,
      right: Math.max(coords.left, endCoords.left),
      bottom: Math.max(coords.bottom, endCoords.bottom) + margin
    }
    var scrollPos = calculateScrollPos(cm, rect)
    var startTop = cm.doc.scrollTop; var startLeft = cm.doc.scrollLeft
    if (scrollPos.scrollTop != null) {
      updateScrollTop(cm, scrollPos.scrollTop)
      if (Math.abs(cm.doc.scrollTop - startTop) > 1) {
        changed = true
      }
    }
    if (scrollPos.scrollLeft != null) {
      setScrollLeft(cm, scrollPos.scrollLeft)
      if (Math.abs(cm.doc.scrollLeft - startLeft) > 1) {
        changed = true
      }
    }
    if (!changed) {
      break
    }
  }
  return rect
}

// Scroll a given set of coordinates into view (immediately).
function scrollIntoView (cm, rect) {
  var scrollPos = calculateScrollPos(cm, rect)
  if (scrollPos.scrollTop != null) {
    updateScrollTop(cm, scrollPos.scrollTop)
  }
  if (scrollPos.scrollLeft != null) {
    setScrollLeft(cm, scrollPos.scrollLeft)
  }
}

// Calculate a new scroll position needed to scroll the given
// rectangle into view. Returns an object with scrollTop and
// scrollLeft properties. When these are undefined, the
// vertical/horizontal position does not need to be adjusted.
function calculateScrollPos (cm, rect) {
  var display = cm.display; var snapMargin = textHeight(cm.display)
  if (rect.top < 0) {
    rect.top = 0
  }
  var screentop = cm.curOp && cm.curOp.scrollTop != null ? cm.curOp.scrollTop : display.scroller.scrollTop
  var screen = displayHeight(cm); var result = {}
  if (rect.bottom - rect.top > screen) {
    rect.bottom = rect.top + screen
  }
  var docBottom = cm.doc.height + paddingVert(display)
  var atTop = rect.top < snapMargin; var atBottom = rect.bottom > docBottom - snapMargin
  if (rect.top < screentop) {
    result.scrollTop = atTop ? 0 : rect.top
  } else if (rect.bottom > screentop + screen) {
    var newTop = Math.min(rect.top, (atBottom ? docBottom : rect.bottom) - screen)
    if (newTop != screentop) {
      result.scrollTop = newTop
    }
  }

  var screenleft = cm.curOp && cm.curOp.scrollLeft != null ? cm.curOp.scrollLeft : display.scroller.scrollLeft
  var screenw = displayWidth(cm) - (cm.options.fixedGutter ? display.gutters.offsetWidth : 0)
  var tooWide = rect.right - rect.left > screenw
  if (tooWide) {
    rect.right = rect.left + screenw
  }
  if (rect.left < 10) {
    result.scrollLeft = 0
  } else if (rect.left < screenleft) {
    result.scrollLeft = Math.max(0, rect.left - (tooWide ? 0 : 10))
  } else if (rect.right > screenw + screenleft - 3) {
    result.scrollLeft = rect.right + (tooWide ? 0 : 10) - screenw
  }
  return result
}

// Store a relative adjustment to the scroll position in the current
// operation (to be applied when the operation finishes).
function addToScrollTop (cm, top) {
  if (top == null) {
    return
  }
  resolveScrollToPos(cm)
  cm.curOp.scrollTop = (cm.curOp.scrollTop == null ? cm.doc.scrollTop : cm.curOp.scrollTop) + top
}

// Make sure that at the end of the operation the current cursor is
// shown.
function ensureCursorVisible (cm) {
  resolveScrollToPos(cm)
  var cur = cm.getCursor()
  cm.curOp.scrollToPos = { from: cur, to: cur, margin: cm.options.cursorScrollMargin }
}

function scrollToCoords (cm, x, y) {
  if (x != null || y != null) {
    resolveScrollToPos(cm)
  }
  if (x != null) {
    cm.curOp.scrollLeft = x
  }
  if (y != null) {
    cm.curOp.scrollTop = y
  }
}

function scrollToRange (cm, range$$1) {
  resolveScrollToPos(cm)
  cm.curOp.scrollToPos = range$$1
}

// When an operation has its scrollToPos property set, and another
// scroll action is applied before the end of the operation, this
// 'simulates' scrolling that position into view in a cheap way, so
// that the effect of intermediate scroll commands is not ignored.
function resolveScrollToPos (cm) {
  var range$$1 = cm.curOp.scrollToPos
  if (range$$1) {
    cm.curOp.scrollToPos = null
    var from = estimateCoords(cm, range$$1.from); var to = estimateCoords(cm, range$$1.to)
    scrollToCoordsRange(cm, from, to, range$$1.margin)
  }
}

function scrollToCoordsRange (cm, from, to, margin) {
  var sPos = calculateScrollPos(cm, {
    left: Math.min(from.left, to.left),
    top: Math.min(from.top, to.top) - margin,
    right: Math.max(from.right, to.right),
    bottom: Math.max(from.bottom, to.bottom) + margin
  })
  scrollToCoords(cm, sPos.scrollLeft, sPos.scrollTop)
}

// Sync the scrollable area and scrollbars, ensure the viewport
// covers the visible area.
function updateScrollTop (cm, val) {
  if (Math.abs(cm.doc.scrollTop - val) < 2) {
    return
  }
  if (!gecko) {
    updateDisplaySimple(cm, { top: val })
  }
  setScrollTop(cm, val, true)
  if (gecko) {
    updateDisplaySimple(cm)
  }
  startWorker(cm, 100)
}

function setScrollTop (cm, val, forceScroll) {
  val = Math.min(cm.display.scroller.scrollHeight - cm.display.scroller.clientHeight, val)
  if (cm.display.scroller.scrollTop == val && !forceScroll) {
    return
  }
  cm.doc.scrollTop = val
  cm.display.scrollbars.setScrollTop(val)
  if (cm.display.scroller.scrollTop != val) {
    cm.display.scroller.scrollTop = val
  }
}

// Sync scroller and scrollbar, ensure the gutter elements are
// aligned.
function setScrollLeft (cm, val, isScroller, forceScroll) {
  val = Math.min(val, cm.display.scroller.scrollWidth - cm.display.scroller.clientWidth)
  if ((isScroller ? val == cm.doc.scrollLeft : Math.abs(cm.doc.scrollLeft - val) < 2) && !forceScroll) {
    return
  }
  cm.doc.scrollLeft = val
  alignHorizontally(cm)
  if (cm.display.scroller.scrollLeft != val) {
    cm.display.scroller.scrollLeft = val
  }
  cm.display.scrollbars.setScrollLeft(val)
}

// SCROLLBARS

// Prepare DOM reads needed to update the scrollbars. Done in one
// shot to minimize update/measure roundtrips.
function measureForScrollbars (cm) {
  var d = cm.display; var gutterW = d.gutters.offsetWidth
  var docH = Math.round(cm.doc.height + paddingVert(cm.display))
  return {
    clientHeight: d.scroller.clientHeight,
    viewHeight: d.wrapper.clientHeight,
    scrollWidth: d.scroller.scrollWidth,
    clientWidth: d.scroller.clientWidth,
    viewWidth: d.wrapper.clientWidth,
    barLeft: cm.options.fixedGutter ? gutterW : 0,
    docHeight: docH,
    scrollHeight: docH + scrollGap(cm) + d.barHeight,
    nativeBarWidth: d.nativeBarWidth,
    gutterWidth: gutterW
  }
}

var NativeScrollbars = function (place, scroll, cm) {
  this.cm = cm
  var vert = this.vert = elt('div', [elt('div', null, null, 'min-width: 1px')], 'CodeMirror-vscrollbar')
  var horiz = this.horiz = elt('div', [elt('div', null, null, 'height: 100%; min-height: 1px')], 'CodeMirror-hscrollbar')
  vert.tabIndex = horiz.tabIndex = -1
  place(vert)
  place(horiz)

  on(vert, 'scroll', function () {
    if (vert.clientHeight) {
      scroll(vert.scrollTop, 'vertical')
    }
  })
  on(horiz, 'scroll', function () {
    if (horiz.clientWidth) {
      scroll(horiz.scrollLeft, 'horizontal')
    }
  })

  this.checkedZeroWidth = false
  // Need to set a minimum width to see the scrollbar on IE7 (but must not set it on IE8).
  if (ie && ie_version < 8) {
    this.horiz.style.minHeight = this.vert.style.minWidth = '18px'
  }
}

NativeScrollbars.prototype.update = function (measure) {
  var needsH = measure.scrollWidth > measure.clientWidth + 1
  var needsV = measure.scrollHeight > measure.clientHeight + 1
  var sWidth = measure.nativeBarWidth

  if (needsV) {
    this.vert.style.display = 'block'
    this.vert.style.bottom = needsH ? sWidth + 'px' : '0'
    var totalHeight = measure.viewHeight - (needsH ? sWidth : 0)
    // A bug in IE8 can cause this value to be negative, so guard it.
    this.vert.firstChild.style.height =
            Math.max(0, measure.scrollHeight - measure.clientHeight + totalHeight) + 'px'
  } else {
    this.vert.style.display = ''
    this.vert.firstChild.style.height = '0'
  }

  if (needsH) {
    this.horiz.style.display = 'block'
    this.horiz.style.right = needsV ? sWidth + 'px' : '0'
    this.horiz.style.left = measure.barLeft + 'px'
    var totalWidth = measure.viewWidth - measure.barLeft - (needsV ? sWidth : 0)
    this.horiz.firstChild.style.width =
            Math.max(0, measure.scrollWidth - measure.clientWidth + totalWidth) + 'px'
  } else {
    this.horiz.style.display = ''
    this.horiz.firstChild.style.width = '0'
  }

  if (!this.checkedZeroWidth && measure.clientHeight > 0) {
    if (sWidth == 0) {
      this.zeroWidthHack()
    }
    this.checkedZeroWidth = true
  }

  return { right: needsV ? sWidth : 0, bottom: needsH ? sWidth : 0 }
}

NativeScrollbars.prototype.setScrollLeft = function (pos) {
  if (this.horiz.scrollLeft != pos) {
    this.horiz.scrollLeft = pos
  }
  if (this.disableHoriz) {
    this.enableZeroWidthBar(this.horiz, this.disableHoriz, 'horiz')
  }
}

NativeScrollbars.prototype.setScrollTop = function (pos) {
  if (this.vert.scrollTop != pos) {
    this.vert.scrollTop = pos
  }
  if (this.disableVert) {
    this.enableZeroWidthBar(this.vert, this.disableVert, 'vert')
  }
}

NativeScrollbars.prototype.zeroWidthHack = function () {
  var w = mac && !mac_geMountainLion ? '12px' : '18px'
  this.horiz.style.height = this.vert.style.width = w
  this.horiz.style.pointerEvents = this.vert.style.pointerEvents = 'none'
  this.disableHoriz = new Delayed()
  this.disableVert = new Delayed()
}

NativeScrollbars.prototype.enableZeroWidthBar = function (bar, delay, type) {
  bar.style.pointerEvents = 'auto'

  function maybeDisable () {
    // To find out whether the scrollbar is still visible, we
    // check whether the element under the pixel in the bottom
    // right corner of the scrollbar box is the scrollbar box
    // itself (when the bar is still visible) or its filler child
    // (when the bar is hidden). If it is still visible, we keep
    // it enabled, if it's hidden, we disable pointer events.
    var box = bar.getBoundingClientRect()
    var elt$$1 = type == 'vert' ? document.elementFromPoint(box.right - 1, (box.top + box.bottom) / 2)
      : document.elementFromPoint((box.right + box.left) / 2, box.bottom - 1)
    if (elt$$1 != bar) {
      bar.style.pointerEvents = 'none'
    } else {
      delay.set(1000, maybeDisable)
    }
  }

  delay.set(1000, maybeDisable)
}

NativeScrollbars.prototype.clear = function () {
  var parent = this.horiz.parentNode
  parent.removeChild(this.horiz)
  parent.removeChild(this.vert)
}

var NullScrollbars = function () {
}

NullScrollbars.prototype.update = function () {
  return { bottom: 0, right: 0 }
}
NullScrollbars.prototype.setScrollLeft = function () {
}
NullScrollbars.prototype.setScrollTop = function () {
}
NullScrollbars.prototype.clear = function () {
}

function updateScrollbars (cm, measure) {
  if (!measure) {
    measure = measureForScrollbars(cm)
  }
  var startWidth = cm.display.barWidth; var startHeight = cm.display.barHeight
  updateScrollbarsInner(cm, measure)
  for (var i = 0; i < 4 && startWidth != cm.display.barWidth || startHeight != cm.display.barHeight; i++) {
    if (startWidth != cm.display.barWidth && cm.options.lineWrapping) {
      updateHeightsInViewport(cm)
    }
    updateScrollbarsInner(cm, measureForScrollbars(cm))
    startWidth = cm.display.barWidth
    startHeight = cm.display.barHeight
  }
}

// Re-synchronize the fake scrollbars with the actual size of the
// content.
function updateScrollbarsInner (cm, measure) {
  var d = cm.display
  var sizes = d.scrollbars.update(measure)

  d.sizer.style.paddingRight = (d.barWidth = sizes.right) + 'px'
  d.sizer.style.paddingBottom = (d.barHeight = sizes.bottom) + 'px'
  d.heightForcer.style.borderBottom = sizes.bottom + 'px solid transparent'

  if (sizes.right && sizes.bottom) {
    d.scrollbarFiller.style.display = 'block'
    d.scrollbarFiller.style.height = sizes.bottom + 'px'
    d.scrollbarFiller.style.width = sizes.right + 'px'
  } else {
    d.scrollbarFiller.style.display = ''
  }
  if (sizes.bottom && cm.options.coverGutterNextToScrollbar && cm.options.fixedGutter) {
    d.gutterFiller.style.display = 'block'
    d.gutterFiller.style.height = sizes.bottom + 'px'
    d.gutterFiller.style.width = measure.gutterWidth + 'px'
  } else {
    d.gutterFiller.style.display = ''
  }
}

var scrollbarModel = { native: NativeScrollbars, null: NullScrollbars }

function initScrollbars (cm) {
  if (cm.display.scrollbars) {
    cm.display.scrollbars.clear()
    if (cm.display.scrollbars.addClass) {
      rmClass(cm.display.wrapper, cm.display.scrollbars.addClass)
    }
  }

  cm.display.scrollbars = new scrollbarModel[cm.options.scrollbarStyle](function (node) {
    cm.display.wrapper.insertBefore(node, cm.display.scrollbarFiller)
    // Prevent clicks in the scrollbars from killing focus
    on(node, 'mousedown', function () {
      if (cm.state.focused) {
        setTimeout(function () {
          return cm.display.input.focus()
        }, 0)
      }
    })
    node.setAttribute('cm-not-content', 'true')
  }, function (pos, axis) {
    if (axis == 'horizontal') {
      setScrollLeft(cm, pos)
    } else {
      updateScrollTop(cm, pos)
    }
  }, cm)
  if (cm.display.scrollbars.addClass) {
    addClass(cm.display.wrapper, cm.display.scrollbars.addClass)
  }
}

// Operations are used to wrap a series of changes to the src
// state in such a way that each change won't have to update the
// cursor and display (which would be awkward, slow, and
// error-prone). Instead, display updates are batched and then all
// combined and executed at once.

var nextOpId = 0

// Start a new operation.
function startOperation (cm) {
  cm.curOp = {
    cm: cm,
    viewChanged: false, // Flag that indicates that lines might need to be redrawn
    startHeight: cm.doc.height, // Used to detect need to update scrollbar
    forceUpdate: false, // Used to force a redraw
    updateInput: 0, // Whether to reset the input textarea
    typing: false, // Whether this reset should be careful to leave existing text (for compositing)
    changeObjs: null, // Accumulated changes, for firing change events
    cursorActivityHandlers: null, // Set of handlers to fire cursorActivity on
    cursorActivityCalled: 0, // Tracks which cursorActivity handlers have been called already
    selectionChanged: false, // Whether the selection needs to be redrawn
    updateMaxLine: false, // Set when the widest line needs to be determined anew
    scrollLeft: null,
    scrollTop: null, // Intermediate scroll position, not pushed to DOM yet
    scrollToPos: null, // Used to scroll to a specific position
    focus: false,
    id: ++nextOpId // Unique ID
  }
  pushOperation(cm.curOp)
}

// Finish an operation, updating the display and signalling delayed events
function endOperation (cm) {
  var op = cm.curOp
  if (op) {
    finishOperation(op, function (group) {
      for (var i = 0; i < group.ops.length; i++) {
        group.ops[i].cm.curOp = null
      }
      endOperations(group)
    })
  }
}

// The DOM updates done when an operation finishes are batched so
// that the minimum number of relayouts are required.
function endOperations (group) {
  var ops = group.ops
  for (var i = 0; i < ops.length; i++) // Read DOM
  {
    endOperation_R1(ops[i])
  }
  for (var i$1 = 0; i$1 < ops.length; i$1++) // Write DOM (maybe)
  {
    endOperation_W1(ops[i$1])
  }
  for (var i$2 = 0; i$2 < ops.length; i$2++) // Read DOM
  {
    endOperation_R2(ops[i$2])
  }
  for (var i$3 = 0; i$3 < ops.length; i$3++) // Write DOM (maybe)
  {
    endOperation_W2(ops[i$3])
  }
  for (var i$4 = 0; i$4 < ops.length; i$4++) // Read DOM
  {
    endOperation_finish(ops[i$4])
  }
}

function endOperation_R1 (op) {
  var cm = op.cm; var display = cm.display
  maybeClipScrollbars(cm)
  if (op.updateMaxLine) {
    findMaxLine(cm)
  }

  op.mustUpdate = op.viewChanged || op.forceUpdate || op.scrollTop != null ||
        op.scrollToPos && (op.scrollToPos.from.line < display.viewFrom ||
            op.scrollToPos.to.line >= display.viewTo) ||
        display.maxLineChanged && cm.options.lineWrapping
  op.update = op.mustUpdate &&
        new DisplayUpdate(cm, op.mustUpdate && { top: op.scrollTop, ensure: op.scrollToPos }, op.forceUpdate)
}

function endOperation_W1 (op) {
  op.updatedDisplay = op.mustUpdate && updateDisplayIfNeeded(op.cm, op.update)
}

function endOperation_R2 (op) {
  var cm = op.cm; var display = cm.display
  if (op.updatedDisplay) {
    updateHeightsInViewport(cm)
  }

  op.barMeasure = measureForScrollbars(cm)

  // If the max line changed since it was last measured, measure it,
  // and ensure the document's width matches it.
  // updateDisplay_W2 will use these properties to do the actual resizing
  if (display.maxLineChanged && !cm.options.lineWrapping) {
    op.adjustWidthTo = measureChar(cm, display.maxLine, display.maxLine.text.length).left + 3
    cm.display.sizerWidth = op.adjustWidthTo
    op.barMeasure.scrollWidth =
            Math.max(display.scroller.clientWidth, display.sizer.offsetLeft + op.adjustWidthTo + scrollGap(cm) + cm.display.barWidth)
    op.maxScrollLeft = Math.max(0, display.sizer.offsetLeft + op.adjustWidthTo - displayWidth(cm))
  }

  if (op.updatedDisplay || op.selectionChanged) {
    op.preparedSelection = display.input.prepareSelection()
  }
}

function endOperation_W2 (op) {
  var cm = op.cm

  if (op.adjustWidthTo != null) {
    cm.display.sizer.style.minWidth = op.adjustWidthTo + 'px'
    if (op.maxScrollLeft < cm.doc.scrollLeft) {
      setScrollLeft(cm, Math.min(cm.display.scroller.scrollLeft, op.maxScrollLeft), true)
    }
    cm.display.maxLineChanged = false
  }

  var takeFocus = op.focus && op.focus == activeElt()
  if (op.preparedSelection) {
    cm.display.input.showSelection(op.preparedSelection, takeFocus)
  }
  if (op.updatedDisplay || op.startHeight != cm.doc.height) {
    updateScrollbars(cm, op.barMeasure)
  }
  if (op.updatedDisplay) {
    setDocumentHeight(cm, op.barMeasure)
  }

  if (op.selectionChanged) {
    restartBlink(cm)
  }

  if (cm.state.focused && op.updateInput) {
    cm.display.input.reset(op.typing)
  }
  if (takeFocus) {
    ensureFocus(op.cm)
  }
}

function endOperation_finish (op) {
  var cm = op.cm; var display = cm.display; var doc = cm.doc

  if (op.updatedDisplay) {
    postUpdateDisplay(cm, op.update)
  }

  // Abort mouse wheel delta measurement, when scrolling explicitly
  if (display.wheelStartX != null && (op.scrollTop != null || op.scrollLeft != null || op.scrollToPos)) {
    display.wheelStartX = display.wheelStartY = null
  }

  // Propagate the scroll position to the actual DOM scroller
  if (op.scrollTop != null) {
    setScrollTop(cm, op.scrollTop, op.forceScroll)
  }

  if (op.scrollLeft != null) {
    setScrollLeft(cm, op.scrollLeft, true, true)
  }
  // If we need to scroll a specific position into view, do so.
  if (op.scrollToPos) {
    var rect = scrollPosIntoView(cm, clipPos(doc, op.scrollToPos.from),
      clipPos(doc, op.scrollToPos.to), op.scrollToPos.margin)
    maybeScrollWindow(cm, rect)
  }

  // Fire events for markers that are hidden/unidden by editing or
  // undoing
  var hidden = op.maybeHiddenMarkers; var unhidden = op.maybeUnhiddenMarkers
  if (hidden) {
    for (var i = 0; i < hidden.length; ++i) {
      if (!hidden[i].lines.length) {
        signal(hidden[i], 'hide')
      }
    }
  }
  if (unhidden) {
    for (var i$1 = 0; i$1 < unhidden.length; ++i$1) {
      if (unhidden[i$1].lines.length) {
        signal(unhidden[i$1], 'unhide')
      }
    }
  }

  if (display.wrapper.offsetHeight) {
    doc.scrollTop = cm.display.scroller.scrollTop
  }

  // Fire change events, and delayed event handlers
  if (op.changeObjs) {
    signal(cm, 'changes', cm, op.changeObjs)
  }
  if (op.update) {
    op.update.finish()
  }
}

// Run the given function in an operation
function runInOp (cm, f) {
  if (cm.curOp) {
    return f()
  }
  startOperation(cm)
  try {
    return f()
  } finally {
    endOperation(cm)
  }
}

// Wraps a function in an operation. Returns the wrapped function.
function operation (cm, f) {
  return function () {
    if (cm.curOp) {
      return f.apply(cm, arguments)
    }
    startOperation(cm)
    try {
      return f.apply(cm, arguments)
    } finally {
      endOperation(cm)
    }
  }
}

// Used to add methods to src and docs instances, wrapping them in
// operations.
function methodOp (f) {
  return function () {
    if (this.curOp) {
      return f.apply(this, arguments)
    }
    startOperation(this)
    try {
      return f.apply(this, arguments)
    } finally {
      endOperation(this)
    }
  }
}

function docMethodOp (f) {
  return function () {
    var cm = this.cm
    if (!cm || cm.curOp) {
      return f.apply(this, arguments)
    }
    startOperation(cm)
    try {
      return f.apply(this, arguments)
    } finally {
      endOperation(cm)
    }
  }
}

// HIGHLIGHT WORKER

function startWorker (cm, time) {
  if (cm.doc.highlightFrontier < cm.display.viewTo) {
    cm.state.highlight.set(time, bind(highlightWorker, cm))
  }
}

function highlightWorker (cm) {
  var doc = cm.doc
  if (doc.highlightFrontier >= cm.display.viewTo) {
    return
  }
  var end = +new Date() + cm.options.workTime
  var context = getContextBefore(cm, doc.highlightFrontier)
  var changedLines = []

  doc.iter(context.line, Math.min(doc.first + doc.size, cm.display.viewTo + 500), function (line) {
    if (context.line >= cm.display.viewFrom) { // Visible
      var oldStyles = line.styles
      var resetState = line.text.length > cm.options.maxHighlightLength ? copyState(doc.mode, context.state) : null
      var highlighted = highlightLine(cm, line, context, true)
      if (resetState) {
        context.state = resetState
      }
      line.styles = highlighted.styles
      var oldCls = line.styleClasses; var newCls = highlighted.classes
      if (newCls) {
        line.styleClasses = newCls
      } else if (oldCls) {
        line.styleClasses = null
      }
      var ischange = !oldStyles || oldStyles.length != line.styles.length ||
                oldCls != newCls && (!oldCls || !newCls || oldCls.bgClass != newCls.bgClass || oldCls.textClass != newCls.textClass)
      for (var i = 0; !ischange && i < oldStyles.length; ++i) {
        ischange = oldStyles[i] != line.styles[i]
      }
      if (ischange) {
        changedLines.push(context.line)
      }
      line.stateAfter = context.save()
      context.nextLine()
    } else {
      if (line.text.length <= cm.options.maxHighlightLength) {
        processLine(cm, line.text, context)
      }
      line.stateAfter = context.line % 5 == 0 ? context.save() : null
      context.nextLine()
    }
    if (+new Date() > end) {
      startWorker(cm, cm.options.workDelay)
      return true
    }
  })
  doc.highlightFrontier = context.line
  doc.modeFrontier = Math.max(doc.modeFrontier, context.line)
  if (changedLines.length) {
    runInOp(cm, function () {
      for (var i = 0; i < changedLines.length; i++) {
        regLineChange(cm, changedLines[i], 'text')
      }
    })
  }
}

// DISPLAY DRAWING

var DisplayUpdate = function (cm, viewport, force) {
  var display = cm.display

  this.viewport = viewport
  // Store some values that we'll need later (but don't want to force a relayout for)
  this.visible = visibleLines(display, cm.doc, viewport)
  this.editorIsHidden = !display.wrapper.offsetWidth
  this.wrapperHeight = display.wrapper.clientHeight
  this.wrapperWidth = display.wrapper.clientWidth
  this.oldDisplayWidth = displayWidth(cm)
  this.force = force
  this.dims = getDimensions(cm)
  this.events = []
}

DisplayUpdate.prototype.signal = function (emitter, type) {
  if (hasHandler(emitter, type)) {
    this.events.push(arguments)
  }
}
DisplayUpdate.prototype.finish = function () {
  var this$1 = this

  for (var i = 0; i < this.events.length; i++) {
    signal.apply(null, this$1.events[i])
  }
}

function maybeClipScrollbars (cm) {
  var display = cm.display
  if (!display.scrollbarsClipped && display.scroller.offsetWidth) {
    display.nativeBarWidth = display.scroller.offsetWidth - display.scroller.clientWidth
    display.heightForcer.style.height = scrollGap(cm) + 'px'
    display.sizer.style.marginBottom = -display.nativeBarWidth + 'px'
    display.sizer.style.borderRightWidth = scrollGap(cm) + 'px'
    display.scrollbarsClipped = true
  }
}

function selectionSnapshot (cm) {
  if (cm.hasFocus()) {
    return null
  }
  var active = activeElt()
  if (!active || !contains(cm.display.lineDiv, active)) {
    return null
  }
  var result = { activeElt: active }
  if (window.getSelection) {
    var sel = window.getSelection()
    if (sel.anchorNode && sel.extend && contains(cm.display.lineDiv, sel.anchorNode)) {
      result.anchorNode = sel.anchorNode
      result.anchorOffset = sel.anchorOffset
      result.focusNode = sel.focusNode
      result.focusOffset = sel.focusOffset
    }
  }
  return result
}

function restoreSelection (snapshot) {
  if (!snapshot || !snapshot.activeElt || snapshot.activeElt == activeElt()) {
    return
  }
  snapshot.activeElt.focus()
  if (snapshot.anchorNode && contains(document.body, snapshot.anchorNode) && contains(document.body, snapshot.focusNode)) {
    var sel = window.getSelection(); var range$$1 = document.createRange()
    range$$1.setEnd(snapshot.anchorNode, snapshot.anchorOffset)
    range$$1.collapse(false)
    sel.removeAllRanges()
    sel.addRange(range$$1)
    sel.extend(snapshot.focusNode, snapshot.focusOffset)
  }
}

// Does the actual updating of the line display. Bails out
// (returning false) when there is nothing to be done and forced is
// false.
function updateDisplayIfNeeded (cm, update) {
  var display = cm.display; var doc = cm.doc

  if (update.editorIsHidden) {
    resetView(cm)
    return false
  }

  // Bail out if the visible area is already rendered and nothing changed.
  if (!update.force &&
        update.visible.from >= display.viewFrom && update.visible.to <= display.viewTo &&
        (display.updateLineNumbers == null || display.updateLineNumbers >= display.viewTo) &&
        display.renderedView == display.view && countDirtyView(cm) == 0) {
    return false
  }

  if (maybeUpdateLineNumberWidth(cm)) {
    resetView(cm)
    update.dims = getDimensions(cm)
  }

  // Compute a suitable new viewport (from & to)
  var end = doc.first + doc.size
  var from = Math.max(update.visible.from - cm.options.viewportMargin, doc.first)
  var to = Math.min(end, update.visible.to + cm.options.viewportMargin)
  if (display.viewFrom < from && from - display.viewFrom < 20) {
    from = Math.max(doc.first, display.viewFrom)
  }
  if (display.viewTo > to && display.viewTo - to < 20) {
    to = Math.min(end, display.viewTo)
  }
  if (sawCollapsedSpans) {
    from = visualLineNo(cm.doc, from)
    to = visualLineEndNo(cm.doc, to)
  }

  var different = from != display.viewFrom || to != display.viewTo ||
        display.lastWrapHeight != update.wrapperHeight || display.lastWrapWidth != update.wrapperWidth
  adjustView(cm, from, to)

  display.viewOffset = heightAtLine(getLine(cm.doc, display.viewFrom))
  // Position the mover div to align with the current scroll position
  cm.display.mover.style.top = display.viewOffset + 'px'

  var toUpdate = countDirtyView(cm)
  if (!different && toUpdate == 0 && !update.force && display.renderedView == display.view &&
        (display.updateLineNumbers == null || display.updateLineNumbers >= display.viewTo)) {
    return false
  }

  // For big changes, we hide the enclosing element during the
  // update, since that speeds up the operations on most browsers.
  var selSnapshot = selectionSnapshot(cm)
  if (toUpdate > 4) {
    display.lineDiv.style.display = 'none'
  }
  patchDisplay(cm, display.updateLineNumbers, update.dims)
  if (toUpdate > 4) {
    display.lineDiv.style.display = ''
  }
  display.renderedView = display.view
  // There might have been a widget with a focused element that got
  // hidden or updated, if so re-focus it.
  restoreSelection(selSnapshot)

  // Prevent selection and cursors from interfering with the scroll
  // width and height.
  removeChildren(display.cursorDiv)
  removeChildren(display.selectionDiv)
  display.gutters.style.height = display.sizer.style.minHeight = 0

  if (different) {
    display.lastWrapHeight = update.wrapperHeight
    display.lastWrapWidth = update.wrapperWidth
    startWorker(cm, 400)
  }

  display.updateLineNumbers = null

  return true
}

function postUpdateDisplay (cm, update) {
  var viewport = update.viewport

  for (var first = true; ; first = false) {
    if (!first || !cm.options.lineWrapping || update.oldDisplayWidth == displayWidth(cm)) {
      // Clip forced viewport to actual scrollable area.
      if (viewport && viewport.top != null) {
        viewport = { top: Math.min(cm.doc.height + paddingVert(cm.display) - displayHeight(cm), viewport.top) }
      }
      // Updated line heights might result in the drawn area not
      // actually covering the viewport. Keep looping until it does.
      update.visible = visibleLines(cm.display, cm.doc, viewport)
      if (update.visible.from >= cm.display.viewFrom && update.visible.to <= cm.display.viewTo) {
        break
      }
    }
    if (!updateDisplayIfNeeded(cm, update)) {
      break
    }
    updateHeightsInViewport(cm)
    var barMeasure = measureForScrollbars(cm)
    updateSelection(cm)
    updateScrollbars(cm, barMeasure)
    setDocumentHeight(cm, barMeasure)
    update.force = false
  }

  update.signal(cm, 'update', cm)
  if (cm.display.viewFrom != cm.display.reportedViewFrom || cm.display.viewTo != cm.display.reportedViewTo) {
    update.signal(cm, 'viewportChange', cm, cm.display.viewFrom, cm.display.viewTo)
    cm.display.reportedViewFrom = cm.display.viewFrom
    cm.display.reportedViewTo = cm.display.viewTo
  }
}

function updateDisplaySimple (cm, viewport) {
  var update = new DisplayUpdate(cm, viewport)
  if (updateDisplayIfNeeded(cm, update)) {
    updateHeightsInViewport(cm)
    postUpdateDisplay(cm, update)
    var barMeasure = measureForScrollbars(cm)
    updateSelection(cm)
    updateScrollbars(cm, barMeasure)
    setDocumentHeight(cm, barMeasure)
    update.finish()
  }
}

// Sync the actual display DOM structure with display.view, removing
// nodes for lines that are no longer in view, and creating the ones
// that are not there yet, and updating the ones that are out of
// date.
function patchDisplay (cm, updateNumbersFrom, dims) {
  var display = cm.display; var lineNumbers = cm.options.lineNumbers
  var container = display.lineDiv; var cur = container.firstChild

  function rm (node) {
    var next = node.nextSibling
    // Works around a throw-scroll bug in OS X Webkit
    if (webkit && mac && cm.display.currentWheelTarget == node) {
      node.style.display = 'none'
    } else {
      node.parentNode.removeChild(node)
    }
    return next
  }

  var view = display.view; var lineN = display.viewFrom
  // Loop over the elements in the view, syncing cur (the DOM nodes
  // in display.lineDiv) with the view as we go.
  for (var i = 0; i < view.length; i++) {
    var lineView = view[i]
    if (lineView.hidden) ; else if (!lineView.node || lineView.node.parentNode != container) { // Not drawn yet
      var node = buildLineElement(cm, lineView, lineN, dims)
      container.insertBefore(node, cur)
    } else { // Already drawn
      while (cur != lineView.node) {
        cur = rm(cur)
      }
      var updateNumber = lineNumbers && updateNumbersFrom != null &&
                updateNumbersFrom <= lineN && lineView.lineNumber
      if (lineView.changes) {
        if (indexOf(lineView.changes, 'gutter') > -1) {
          updateNumber = false
        }
        updateLineForChanges(cm, lineView, lineN, dims)
      }
      if (updateNumber) {
        removeChildren(lineView.lineNumber)
        lineView.lineNumber.appendChild(document.createTextNode(lineNumberFor(cm.options, lineN)))
      }
      cur = lineView.node.nextSibling
    }
    lineN += lineView.size
  }
  while (cur) {
    cur = rm(cur)
  }
}

function updateGutterSpace (display) {
  var width = display.gutters.offsetWidth
  display.sizer.style.marginLeft = width + 'px'
}

function setDocumentHeight (cm, measure) {
  cm.display.sizer.style.minHeight = measure.docHeight + 'px'
  cm.display.heightForcer.style.top = measure.docHeight + 'px'
  cm.display.gutters.style.height = (measure.docHeight + cm.display.barHeight + scrollGap(cm)) + 'px'
}

// Re-align line numbers and gutter marks to compensate for
// horizontal scrolling.
function alignHorizontally (cm) {
  var display = cm.display; var view = display.view
  if (!display.alignWidgets && (!display.gutters.firstChild || !cm.options.fixedGutter)) {
    return
  }
  var comp = compensateForHScroll(display) - display.scroller.scrollLeft + cm.doc.scrollLeft
  var gutterW = display.gutters.offsetWidth; var left = comp + 'px'
  for (var i = 0; i < view.length; i++) {
    if (!view[i].hidden) {
      if (cm.options.fixedGutter) {
        if (view[i].gutter) {
          view[i].gutter.style.left = left
        }
        if (view[i].gutterBackground) {
          view[i].gutterBackground.style.left = left
        }
      }
      var align = view[i].alignable
      if (align) {
        for (var j = 0; j < align.length; j++) {
          align[j].style.left = left
        }
      }
    }
  }
  if (cm.options.fixedGutter) {
    display.gutters.style.left = (comp + gutterW) + 'px'
  }
}

// Used to ensure that the line number gutter is still the right
// size for the current document size. Returns true when an update
// is needed.
function maybeUpdateLineNumberWidth (cm) {
  if (!cm.options.lineNumbers) {
    return false
  }
  var doc = cm.doc; var last = lineNumberFor(cm.options, doc.first + doc.size - 1); var display = cm.display
  if (last.length != display.lineNumChars) {
    var test = display.measure.appendChild(elt('div', [elt('div', last)],
      'CodeMirror-linenumber CodeMirror-gutter-elt'))
    var innerW = test.firstChild.offsetWidth; var padding = test.offsetWidth - innerW
    display.lineGutter.style.width = ''
    display.lineNumInnerWidth = Math.max(innerW, display.lineGutter.offsetWidth - padding) + 1
    display.lineNumWidth = display.lineNumInnerWidth + padding
    display.lineNumChars = display.lineNumInnerWidth ? last.length : -1
    display.lineGutter.style.width = display.lineNumWidth + 'px'
    updateGutterSpace(cm.display)
    return true
  }
  return false
}

function getGutters (gutters, lineNumbers) {
  var result = []; var sawLineNumbers = false
  for (var i = 0; i < gutters.length; i++) {
    var name = gutters[i]; var style = null
    if (typeof name !== 'string') {
      style = name.style
      name = name.className
    }
    if (name == 'CodeMirror-linenumbers') {
      if (!lineNumbers) {
        continue
      } else {
        sawLineNumbers = true
      }
    }
    result.push({ className: name, style: style })
  }
  if (lineNumbers && !sawLineNumbers) {
    result.push({ className: 'CodeMirror-linenumbers', style: null })
  }
  return result
}

// Rebuild the gutter elements, ensure the margin to the left of the
// code matches their width.
function renderGutters (display) {
  var gutters = display.gutters; var specs = display.gutterSpecs
  removeChildren(gutters)
  display.lineGutter = null
  for (var i = 0; i < specs.length; ++i) {
    var ref = specs[i]
    var className = ref.className
    var style = ref.style
    var gElt = gutters.appendChild(elt('div', null, 'CodeMirror-gutter ' + className))
    if (style) {
      gElt.style.cssText = style
    }
    if (className == 'CodeMirror-linenumbers') {
      display.lineGutter = gElt
      gElt.style.width = (display.lineNumWidth || 1) + 'px'
    }
  }
  gutters.style.display = specs.length ? '' : 'none'
  updateGutterSpace(display)
}

function updateGutters (cm) {
  renderGutters(cm.display)
  regChange(cm)
  alignHorizontally(cm)
}

// The display handles the DOM integration, both for input reading
// and content drawing. It holds references to DOM nodes and
// display-related state.

function Display (place, doc, input, options) {
  var d = this
  this.input = input

  // Covers bottom-right square when both scrollbars are present.
  d.scrollbarFiller = elt('div', null, 'CodeMirror-scrollbar-filler')
  d.scrollbarFiller.setAttribute('cm-not-content', 'true')
  // Covers bottom of gutter when coverGutterNextToScrollbar is on
  // and h scrollbar is present.
  d.gutterFiller = elt('div', null, 'CodeMirror-gutter-filler')
  d.gutterFiller.setAttribute('cm-not-content', 'true')
  // Will contain the actual code, positioned to cover the viewport.
  d.lineDiv = eltP('div', null, 'CodeMirror-code')
  // Elements are added to these to represent selection and cursors.
  d.selectionDiv = elt('div', null, null, 'position: relative; z-index: 1')
  d.cursorDiv = elt('div', null, 'CodeMirror-cursors')
  // A visibility: hidden element used to find the size of things.
  d.measure = elt('div', null, 'CodeMirror-measure')
  // When lines outside of the viewport are measured, they are drawn in this.
  d.lineMeasure = elt('div', null, 'CodeMirror-measure')
  // Wraps everything that needs to exist inside the vertically-padded coordinate system
  d.lineSpace = eltP('div', [d.measure, d.lineMeasure, d.selectionDiv, d.cursorDiv, d.lineDiv],
    null, 'position: relative; outline: none')
  var lines = eltP('div', [d.lineSpace], 'CodeMirror-lines')
  // Moved around its parent to cover visible view.
  d.mover = elt('div', [lines], null, 'position: relative')
  // Set to the height of the document, allowing scrolling.
  d.sizer = elt('div', [d.mover], 'CodeMirror-sizer')
  d.sizerWidth = null
  // Behavior of elts with overflow: auto and padding is
  // inconsistent across browsers. This is used to ensure the
  // scrollable area is big enough.
  d.heightForcer = elt('div', null, null, 'position: absolute; height: ' + scrollerGap + 'px; width: 1px;')
  // Will contain the gutters, if any.
  d.gutters = elt('div', null, 'CodeMirror-gutters')
  d.lineGutter = null
  // Actual scrollable element.
  d.scroller = elt('div', [d.sizer, d.heightForcer, d.gutters], 'CodeMirror-scroll')
  d.scroller.setAttribute('tabIndex', '-1')
  // The element in which the src lives.
  d.wrapper = elt('div', [d.scrollbarFiller, d.gutterFiller, d.scroller], 'CodeMirror')

  // Work around IE7 z-index bug (not perfect, hence IE7 not really being supported)
  if (ie && ie_version < 8) {
    d.gutters.style.zIndex = -1
    d.scroller.style.paddingRight = 0
  }
  if (!webkit && !(gecko && mobile)) {
    d.scroller.draggable = true
  }

  if (place) {
    if (place.appendChild) {
      place.appendChild(d.wrapper)
    } else {
      place(d.wrapper)
    }
  }

  // Current rendered range (may be bigger than the view window).
  d.viewFrom = d.viewTo = doc.first
  d.reportedViewFrom = d.reportedViewTo = doc.first
  // Information about the rendered lines.
  d.view = []
  d.renderedView = null
  // Holds info about a single rendered line when it was rendered
  // for measurement, while not in view.
  d.externalMeasured = null
  // Empty space (in pixels) above the view
  d.viewOffset = 0
  d.lastWrapHeight = d.lastWrapWidth = 0
  d.updateLineNumbers = null

  d.nativeBarWidth = d.barHeight = d.barWidth = 0
  d.scrollbarsClipped = false

  // Used to only resize the line number gutter when necessary (when
  // the amount of lines crosses a boundary that makes its width change)
  d.lineNumWidth = d.lineNumInnerWidth = d.lineNumChars = null
  // Set to true when a non-horizontal-scrolling line widget is
  // added. As an optimization, line widget aligning is skipped when
  // this is false.
  d.alignWidgets = false

  d.cachedCharWidth = d.cachedTextHeight = d.cachedPaddingH = null

  // Tracks the maximum line length so that the horizontal scrollbar
  // can be kept static when scrolling.
  d.maxLine = null
  d.maxLineLength = 0
  d.maxLineChanged = false

  // Used for measuring wheel scrolling granularity
  d.wheelDX = d.wheelDY = d.wheelStartX = d.wheelStartY = null

  // True when shift is held down.
  d.shift = false

  // Used to track whether anything happened since the context menu
  // was opened.
  d.selForContextMenu = null

  d.activeTouch = null

  d.gutterSpecs = getGutters(options.gutters, options.lineNumbers)
  renderGutters(d)

  input.init(d)
}

// Since the delta values reported on mouse wheel events are
// unstandardized between browsers and even browser versions, and
// generally horribly unpredictable, this code starts by measuring
// the scroll effect that the first few mouse wheel events have,
// and, from that, detects the way it can convert deltas to pixel
// offsets afterwards.
//
// The reason we want to know the amount a wheel event will scroll
// is that it gives us a chance to update the display before the
// actual scrolling happens, reducing flickering.

var wheelSamples = 0; var wheelPixelsPerUnit = null
// Fill in a browser-detected starting value on browsers where we
// know one. These don't have to be accurate -- the result of them
// being wrong would just be a slight flicker on the first wheel
// scroll (if it is large enough).
if (ie) {
  wheelPixelsPerUnit = -0.53
} else if (gecko) {
  wheelPixelsPerUnit = 15
} else if (chrome) {
  wheelPixelsPerUnit = -0.7
} else if (safari) {
  wheelPixelsPerUnit = -1 / 3
}

function wheelEventDelta (e) {
  var dx = e.wheelDeltaX; var dy = e.wheelDeltaY
  if (dx == null && e.detail && e.axis == e.HORIZONTAL_AXIS) {
    dx = e.detail
  }
  if (dy == null && e.detail && e.axis == e.VERTICAL_AXIS) {
    dy = e.detail
  } else if (dy == null) {
    dy = e.wheelDelta
  }
  return { x: dx, y: dy }
}

function wheelEventPixels (e) {
  var delta = wheelEventDelta(e)
  delta.x *= wheelPixelsPerUnit
  delta.y *= wheelPixelsPerUnit
  return delta
}

function onScrollWheel (cm, e) {
  var delta = wheelEventDelta(e); var dx = delta.x; var dy = delta.y

  var display = cm.display; var scroll = display.scroller
  // Quit if there's nothing to scroll here
  var canScrollX = scroll.scrollWidth > scroll.clientWidth
  var canScrollY = scroll.scrollHeight > scroll.clientHeight
  if (!(dx && canScrollX || dy && canScrollY)) {
    return
  }

  // Webkit browsers on OS X abort momentum scrolls when the target
  // of the scroll event is removed from the scrollable element.
  // This hack (see related code in patchDisplay) makes sure the
  // element is kept around.
  if (dy && mac && webkit) {
    outer: for (var cur = e.target, view = display.view; cur != scroll; cur = cur.parentNode) {
      for (var i = 0; i < view.length; i++) {
        if (view[i].node == cur) {
          cm.display.currentWheelTarget = cur
          break outer
        }
      }
    }
  }

  // On some browsers, horizontal scrolling will cause redraws to
  // happen before the gutter has been realigned, causing it to
  // wriggle around in a most unseemly way. When we have an
  // estimated pixels/delta value, we just handle horizontal
  // scrolling entirely here. It'll be slightly off from native, but
  // better than glitching out.
  if (dx && !gecko && !presto && wheelPixelsPerUnit != null) {
    if (dy && canScrollY) {
      updateScrollTop(cm, Math.max(0, scroll.scrollTop + dy * wheelPixelsPerUnit))
    }
    setScrollLeft(cm, Math.max(0, scroll.scrollLeft + dx * wheelPixelsPerUnit))
    // Only prevent default scrolling if vertical scrolling is
    // actually possible. Otherwise, it causes vertical scroll
    // jitter on OSX trackpads when deltaX is small and deltaY
    // is large (issue #3579)
    if (!dy || (dy && canScrollY)) {
      e_preventDefault(e)
    }
    display.wheelStartX = null // Abort measurement, if in progress
    return
  }

  // 'Project' the visible viewport to cover the area that is being
  // scrolled into view (if we know enough to estimate it).
  if (dy && wheelPixelsPerUnit != null) {
    var pixels = dy * wheelPixelsPerUnit
    var top = cm.doc.scrollTop; var bot = top + display.wrapper.clientHeight
    if (pixels < 0) {
      top = Math.max(0, top + pixels - 50)
    } else {
      bot = Math.min(cm.doc.height, bot + pixels + 50)
    }
    updateDisplaySimple(cm, { top: top, bottom: bot })
  }

  if (wheelSamples < 20) {
    if (display.wheelStartX == null) {
      display.wheelStartX = scroll.scrollLeft
      display.wheelStartY = scroll.scrollTop
      display.wheelDX = dx
      display.wheelDY = dy
      setTimeout(function () {
        if (display.wheelStartX == null) {
          return
        }
        var movedX = scroll.scrollLeft - display.wheelStartX
        var movedY = scroll.scrollTop - display.wheelStartY
        var sample = (movedY && display.wheelDY && movedY / display.wheelDY) ||
                    (movedX && display.wheelDX && movedX / display.wheelDX)
        display.wheelStartX = display.wheelStartY = null
        if (!sample) {
          return
        }
        wheelPixelsPerUnit = (wheelPixelsPerUnit * wheelSamples + sample) / (wheelSamples + 1)
        ++wheelSamples
      }, 200)
    } else {
      display.wheelDX += dx
      display.wheelDY += dy
    }
  }
}

// Selection objects are immutable. A new one is created every time
// the selection changes. A selection is one or more non-overlapping
// (and non-touching) ranges, sorted, and an integer that indicates
// which one is the primary selection (the one that's scrolled into
// view, that getCursor returns, etc).
var Selection = function (ranges, primIndex) {
  this.ranges = ranges
  this.primIndex = primIndex
}

Selection.prototype.primary = function () {
  return this.ranges[this.primIndex]
}

Selection.prototype.equals = function (other) {
  var this$1 = this

  if (other == this) {
    return true
  }
  if (other.primIndex != this.primIndex || other.ranges.length != this.ranges.length) {
    return false
  }
  for (var i = 0; i < this.ranges.length; i++) {
    var here = this$1.ranges[i]; var there = other.ranges[i]
    if (!equalCursorPos(here.anchor, there.anchor) || !equalCursorPos(here.head, there.head)) {
      return false
    }
  }
  return true
}

Selection.prototype.deepCopy = function () {
  var this$1 = this

  var out = []
  for (var i = 0; i < this.ranges.length; i++) {
    out[i] = new Range(copyPos(this$1.ranges[i].anchor), copyPos(this$1.ranges[i].head))
  }
  return new Selection(out, this.primIndex)
}

Selection.prototype.somethingSelected = function () {
  var this$1 = this

  for (var i = 0; i < this.ranges.length; i++) {
    if (!this$1.ranges[i].empty()) {
      return true
    }
  }
  return false
}

Selection.prototype.contains = function (pos, end) {
  var this$1 = this

  if (!end) {
    end = pos
  }
  for (var i = 0; i < this.ranges.length; i++) {
    var range = this$1.ranges[i]
    if (cmp(end, range.from()) >= 0 && cmp(pos, range.to()) <= 0) {
      return i
    }
  }
  return -1
}

var Range = function (anchor, head) {
  this.anchor = anchor
  this.head = head
}

Range.prototype.from = function () {
  return minPos(this.anchor, this.head)
}
Range.prototype.to = function () {
  return maxPos(this.anchor, this.head)
}
Range.prototype.empty = function () {
  return this.head.line == this.anchor.line && this.head.ch == this.anchor.ch
}

// Take an unsorted, potentially overlapping set of ranges, and
// build a selection out of it. 'Consumes' ranges array (modifying
// it).
function normalizeSelection (cm, ranges, primIndex) {
  var mayTouch = cm && cm.options.selectionsMayTouch
  var prim = ranges[primIndex]
  ranges.sort(function (a, b) {
    return cmp(a.from(), b.from())
  })
  primIndex = indexOf(ranges, prim)
  for (var i = 1; i < ranges.length; i++) {
    var cur = ranges[i]; var prev = ranges[i - 1]
    var diff = cmp(prev.to(), cur.from())
    if (mayTouch && !cur.empty() ? diff > 0 : diff >= 0) {
      var from = minPos(prev.from(), cur.from()); var to = maxPos(prev.to(), cur.to())
      var inv = prev.empty() ? cur.from() == cur.head : prev.from() == prev.head
      if (i <= primIndex) {
        --primIndex
      }
      ranges.splice(--i, 2, new Range(inv ? to : from, inv ? from : to))
    }
  }
  return new Selection(ranges, primIndex)
}

function simpleSelection (anchor, head) {
  return new Selection([new Range(anchor, head || anchor)], 0)
}

// Compute the position of the end of a change (its 'to' property
// refers to the pre-change end).
function changeEnd (change) {
  if (!change.text) {
    return change.to
  }
  return Pos(change.from.line + change.text.length - 1,
    lst(change.text).length + (change.text.length == 1 ? change.from.ch : 0))
}

// Adjust a position to refer to the post-change position of the
// same text, or the end of the change if the change covers it.
function adjustForChange (pos, change) {
  if (cmp(pos, change.from) < 0) {
    return pos
  }
  if (cmp(pos, change.to) <= 0) {
    return changeEnd(change)
  }

  var line = pos.line + change.text.length - (change.to.line - change.from.line) - 1; var ch = pos.ch
  if (pos.line == change.to.line) {
    ch += changeEnd(change).ch - change.to.ch
  }
  return Pos(line, ch)
}

function computeSelAfterChange (doc, change) {
  var out = []
  for (var i = 0; i < doc.sel.ranges.length; i++) {
    var range = doc.sel.ranges[i]
    out.push(new Range(adjustForChange(range.anchor, change),
      adjustForChange(range.head, change)))
  }
  return normalizeSelection(doc.cm, out, doc.sel.primIndex)
}

function offsetPos (pos, old, nw) {
  if (pos.line == old.line) {
    return Pos(nw.line, pos.ch - old.ch + nw.ch)
  } else {
    return Pos(nw.line + (pos.line - old.line), pos.ch)
  }
}

// Used by replaceSelections to allow moving the selection to the
// start or around the replaced test. Hint may be "start" or "around".
function computeReplacedSel (doc, changes, hint) {
  var out = []
  var oldPrev = Pos(doc.first, 0); var newPrev = oldPrev
  for (var i = 0; i < changes.length; i++) {
    var change = changes[i]
    var from = offsetPos(change.from, oldPrev, newPrev)
    var to = offsetPos(changeEnd(change), oldPrev, newPrev)
    oldPrev = change.to
    newPrev = to
    if (hint == 'around') {
      var range = doc.sel.ranges[i]; var inv = cmp(range.head, range.anchor) < 0
      out[i] = new Range(inv ? to : from, inv ? from : to)
    } else {
      out[i] = new Range(from, from)
    }
  }
  return new Selection(out, doc.sel.primIndex)
}

// Used to get the src into a consistent state again when options change.

function loadMode (cm) {
  cm.doc.mode = getMode(cm.options, cm.doc.modeOption)
  resetModeState(cm)
}

function resetModeState (cm) {
  cm.doc.iter(function (line) {
    if (line.stateAfter) {
      line.stateAfter = null
    }
    if (line.styles) {
      line.styles = null
    }
  })
  cm.doc.modeFrontier = cm.doc.highlightFrontier = cm.doc.first
  startWorker(cm, 100)
  cm.state.modeGen++
  if (cm.curOp) {
    regChange(cm)
  }
}

// DOCUMENT DATA STRUCTURE

// By default, updates that start and end at the beginning of a line
// are treated specially, in order to make the association of line
// widgets and marker elements with the text behave more intuitive.
function isWholeLineUpdate (doc, change) {
  return change.from.ch == 0 && change.to.ch == 0 && lst(change.text) == '' &&
        (!doc.cm || doc.cm.options.wholeLineUpdateBefore)
}

// Perform a change on the document data structure.
function updateDoc (doc, change, markedSpans, estimateHeight$$1) {
  function spansFor (n) {
    return markedSpans ? markedSpans[n] : null
  }

  function update (line, text, spans) {
    updateLine(line, text, spans, estimateHeight$$1)
    signalLater(line, 'change', line, change)
  }

  function linesFor (start, end) {
    var result = []
    for (var i = start; i < end; ++i) {
      result.push(new Line(text[i], spansFor(i), estimateHeight$$1))
    }
    return result
  }

  var from = change.from; var to = change.to; var text = change.text
  var firstLine = getLine(doc, from.line); var lastLine = getLine(doc, to.line)
  var lastText = lst(text); var lastSpans = spansFor(text.length - 1); var nlines = to.line - from.line

  // Adjust the line structure
  if (change.full) {
    doc.insert(0, linesFor(0, text.length))
    doc.remove(text.length, doc.size - text.length)
  } else if (isWholeLineUpdate(doc, change)) {
    // This is a whole-line replace. Treated specially to make
    // sure line objects move the way they are supposed to.
    var added = linesFor(0, text.length - 1)
    update(lastLine, lastLine.text, lastSpans)
    if (nlines) {
      doc.remove(from.line, nlines)
    }
    if (added.length) {
      doc.insert(from.line, added)
    }
  } else if (firstLine == lastLine) {
    if (text.length == 1) {
      update(firstLine, firstLine.text.slice(0, from.ch) + lastText + firstLine.text.slice(to.ch), lastSpans)
    } else {
      var added$1 = linesFor(1, text.length - 1)
      added$1.push(new Line(lastText + firstLine.text.slice(to.ch), lastSpans, estimateHeight$$1))
      update(firstLine, firstLine.text.slice(0, from.ch) + text[0], spansFor(0))
      doc.insert(from.line + 1, added$1)
    }
  } else if (text.length == 1) {
    update(firstLine, firstLine.text.slice(0, from.ch) + text[0] + lastLine.text.slice(to.ch), spansFor(0))
    doc.remove(from.line + 1, nlines)
  } else {
    update(firstLine, firstLine.text.slice(0, from.ch) + text[0], spansFor(0))
    update(lastLine, lastText + lastLine.text.slice(to.ch), lastSpans)
    var added$2 = linesFor(1, text.length - 1)
    if (nlines > 1) {
      doc.remove(from.line + 1, nlines - 1)
    }
    doc.insert(from.line + 1, added$2)
  }

  signalLater(doc, 'change', doc, change)
}

// Call f for all linked documents.
function linkedDocs (doc, f, sharedHistOnly) {
  function propagate (doc, skip, sharedHist) {
    if (doc.linked) {
      for (var i = 0; i < doc.linked.length; ++i) {
        var rel = doc.linked[i]
        if (rel.doc == skip) {
          continue
        }
        var shared = sharedHist && rel.sharedHist
        if (sharedHistOnly && !shared) {
          continue
        }
        f(rel.doc, shared)
        propagate(rel.doc, doc, shared)
      }
    }
  }

  propagate(doc, null, true)
}

// Attach a document to an src.
function attachDoc (cm, doc) {
  if (doc.cm) {
    throw new Error('This document is already in use.')
  }
  cm.doc = doc
  doc.cm = cm
  estimateLineHeights(cm)
  loadMode(cm)
  setDirectionClass(cm)
  if (!cm.options.lineWrapping) {
    findMaxLine(cm)
  }
  cm.options.mode = doc.modeOption
  regChange(cm)
}

function setDirectionClass (cm) {
  (cm.doc.direction == 'rtl' ? addClass : rmClass)(cm.display.lineDiv, 'CodeMirror-rtl')
}

function directionChanged (cm) {
  runInOp(cm, function () {
    setDirectionClass(cm)
    regChange(cm)
  })
}

function History (startGen) {
  // Arrays of change events and selections. Doing something adds an
  // event to done and clears undo. Undoing moves events from done
  // to undone, redoing moves them in the other direction.
  this.done = []
  this.undone = []
  this.undoDepth = Infinity
  // Used to track when changes can be merged into a single undo
  // event
  this.lastModTime = this.lastSelTime = 0
  this.lastOp = this.lastSelOp = null
  this.lastOrigin = this.lastSelOrigin = null
  // Used by the isClean() method
  this.generation = this.maxGeneration = startGen || 1
}

// Create a history change event from an updateDoc-style change
// object.
function historyChangeFromChange (doc, change) {
  var histChange = { from: copyPos(change.from), to: changeEnd(change), text: getBetween(doc, change.from, change.to) }
  attachLocalSpans(doc, histChange, change.from.line, change.to.line + 1)
  linkedDocs(doc, function (doc) {
    return attachLocalSpans(doc, histChange, change.from.line, change.to.line + 1)
  }, true)
  return histChange
}

// Pop all selection events off the end of a history array. Stop at
// a change event.
function clearSelectionEvents (array) {
  while (array.length) {
    var last = lst(array)
    if (last.ranges) {
      array.pop()
    } else {
      break
    }
  }
}

// Find the top change event in the history. Pop off selection
// events that are in the way.
function lastChangeEvent (hist, force) {
  if (force) {
    clearSelectionEvents(hist.done)
    return lst(hist.done)
  } else if (hist.done.length && !lst(hist.done).ranges) {
    return lst(hist.done)
  } else if (hist.done.length > 1 && !hist.done[hist.done.length - 2].ranges) {
    hist.done.pop()
    return lst(hist.done)
  }
}

// Register a change in the history. Merges changes that are within
// a single operation, or are close together with an origin that
// allows merging (starting with "+") into a single event.
function addChangeToHistory (doc, change, selAfter, opId) {
  var hist = doc.history
  hist.undone.length = 0
  var time = +new Date(); var cur
  var last

  if ((hist.lastOp == opId ||
        hist.lastOrigin == change.origin && change.origin &&
        ((change.origin.charAt(0) == '+' && hist.lastModTime > time - (doc.cm ? doc.cm.options.historyEventDelay : 500)) ||
            change.origin.charAt(0) == '*')) &&
        (cur = lastChangeEvent(hist, hist.lastOp == opId))) {
    // Merge this change into the last event
    last = lst(cur.changes)
    if (cmp(change.from, change.to) == 0 && cmp(change.from, last.to) == 0) {
      // Optimized case for simple insertion -- don't want to add
      // new changesets for every character typed
      last.to = changeEnd(change)
    } else {
      // Add new sub-event
      cur.changes.push(historyChangeFromChange(doc, change))
    }
  } else {
    // Can not be merged, start a new event.
    var before = lst(hist.done)
    if (!before || !before.ranges) {
      pushSelectionToHistory(doc.sel, hist.done)
    }
    cur = {
      changes: [historyChangeFromChange(doc, change)],
      generation: hist.generation
    }
    hist.done.push(cur)
    while (hist.done.length > hist.undoDepth) {
      hist.done.shift()
      if (!hist.done[0].ranges) {
        hist.done.shift()
      }
    }
  }
  hist.done.push(selAfter)
  hist.generation = ++hist.maxGeneration
  hist.lastModTime = hist.lastSelTime = time
  hist.lastOp = hist.lastSelOp = opId
  hist.lastOrigin = hist.lastSelOrigin = change.origin

  if (!last) {
    signal(doc, 'historyAdded')
  }
}

function selectionEventCanBeMerged (doc, origin, prev, sel) {
  var ch = origin.charAt(0)
  return ch == '*' ||
        ch == '+' &&
        prev.ranges.length == sel.ranges.length &&
        prev.somethingSelected() == sel.somethingSelected() &&
        new Date() - doc.history.lastSelTime <= (doc.cm ? doc.cm.options.historyEventDelay : 500)
}

// Called whenever the selection changes, sets the new selection as
// the pending selection in the history, and pushes the old pending
// selection into the 'done' array when it was significantly
// different (in number of selected ranges, emptiness, or time).
function addSelectionToHistory (doc, sel, opId, options) {
  var hist = doc.history; var origin = options && options.origin

  // A new event is started when the previous origin does not match
  // the current, or the origins don't allow matching. Origins
  // starting with * are always merged, those starting with + are
  // merged when similar and close together in time.
  if (opId == hist.lastSelOp ||
        (origin && hist.lastSelOrigin == origin &&
            (hist.lastModTime == hist.lastSelTime && hist.lastOrigin == origin ||
                selectionEventCanBeMerged(doc, origin, lst(hist.done), sel)))) {
    hist.done[hist.done.length - 1] = sel
  } else {
    pushSelectionToHistory(sel, hist.done)
  }

  hist.lastSelTime = +new Date()
  hist.lastSelOrigin = origin
  hist.lastSelOp = opId
  if (options && options.clearRedo !== false) {
    clearSelectionEvents(hist.undone)
  }
}

function pushSelectionToHistory (sel, dest) {
  var top = lst(dest)
  if (!(top && top.ranges && top.equals(sel))) {
    dest.push(sel)
  }
}

// Used to store index span information in the history.
function attachLocalSpans (doc, change, from, to) {
  var existing = change['spans_' + doc.id]; var n = 0
  doc.iter(Math.max(doc.first, from), Math.min(doc.first + doc.size, to), function (line) {
    if (line.markedSpans) {
      (existing || (existing = change['spans_' + doc.id] = {}))[n] = line.markedSpans
    }
    ++n
  })
}

// When un/re-doing restores text containing index spans, those
// that have been explicitly cleared should not be restored.
function removeClearedSpans (spans) {
  if (!spans) {
    return null
  }
  var out
  for (var i = 0; i < spans.length; ++i) {
    if (spans[i].marker.explicitlyCleared) {
      if (!out) {
        out = spans.slice(0, i)
      }
    } else if (out) {
      out.push(spans[i])
    }
  }
  return !out ? spans : out.length ? out : null
}

// Retrieve and filter the old index spans stored in a change event.
function getOldSpans (doc, change) {
  var found = change['spans_' + doc.id]
  if (!found) {
    return null
  }
  var nw = []
  for (var i = 0; i < change.text.length; ++i) {
    nw.push(removeClearedSpans(found[i]))
  }
  return nw
}

// Used for un/re-doing changes from the history. Combines the
// result of computing the existing spans with the set of spans that
// existed in the history (so that deleting around a span and then
// undoing brings back the span).
function mergeOldSpans (doc, change) {
  var old = getOldSpans(doc, change)
  var stretched = stretchSpansOverChange(doc, change)
  if (!old) {
    return stretched
  }
  if (!stretched) {
    return old
  }

  for (var i = 0; i < old.length; ++i) {
    var oldCur = old[i]; var stretchCur = stretched[i]
    if (oldCur && stretchCur) {
      spans: for (var j = 0; j < stretchCur.length; ++j) {
        var span = stretchCur[j]
        for (var k = 0; k < oldCur.length; ++k) {
          if (oldCur[k].marker == span.marker) {
            continue spans
          }
        }
        oldCur.push(span)
      }
    } else if (stretchCur) {
      old[i] = stretchCur
    }
  }
  return old
}

// Used both to provide a JSON-safe object in .getHistory, and, when
// detaching a document, to split the history in two
function copyHistoryArray (events, newGroup, instantiateSel) {
  var copy = []
  for (var i = 0; i < events.length; ++i) {
    var event = events[i]
    if (event.ranges) {
      copy.push(instantiateSel ? Selection.prototype.deepCopy.call(event) : event)
      continue
    }
    var changes = event.changes; var newChanges = []
    copy.push({ changes: newChanges })
    for (var j = 0; j < changes.length; ++j) {
      var change = changes[j]; var m = (void 0)
      newChanges.push({ from: change.from, to: change.to, text: change.text })
      if (newGroup) {
        for (var prop in change) {
          if (m = prop.match(/^spans_(\d+)$/)) {
            if (indexOf(newGroup, Number(m[1])) > -1) {
              lst(newChanges)[prop] = change[prop]
              delete change[prop]
            }
          }
        }
      }
    }
  }
  return copy
}

// The 'scroll' parameter given to many of these indicated whether
// the new cursor position should be scrolled into view after
// modifying the selection.

// If shift is held or the extend flag is set, extends a range to
// include a given position (and optionally a second position).
// Otherwise, simply returns the range between the given positions.
// Used for cursor motion and such.
function extendRange (range, head, other, extend) {
  if (extend) {
    var anchor = range.anchor
    if (other) {
      var posBefore = cmp(head, anchor) < 0
      if (posBefore != (cmp(other, anchor) < 0)) {
        anchor = head
        head = other
      } else if (posBefore != (cmp(head, other) < 0)) {
        head = other
      }
    }
    return new Range(anchor, head)
  } else {
    return new Range(other || head, head)
  }
}

// Extend the primary selection range, discard the rest.
function extendSelection (doc, head, other, options, extend) {
  if (extend == null) {
    extend = doc.cm && (doc.cm.display.shift || doc.extend)
  }
  setSelection(doc, new Selection([extendRange(doc.sel.primary(), head, other, extend)], 0), options)
}

// Extend all selections (pos is an array of selections with length
// equal the number of selections)
function extendSelections (doc, heads, options) {
  var out = []
  var extend = doc.cm && (doc.cm.display.shift || doc.extend)
  for (var i = 0; i < doc.sel.ranges.length; i++) {
    out[i] = extendRange(doc.sel.ranges[i], heads[i], null, extend)
  }
  var newSel = normalizeSelection(doc.cm, out, doc.sel.primIndex)
  setSelection(doc, newSel, options)
}

// Updates a single range in the selection.
function replaceOneSelection (doc, i, range, options) {
  var ranges = doc.sel.ranges.slice(0)
  ranges[i] = range
  setSelection(doc, normalizeSelection(doc.cm, ranges, doc.sel.primIndex), options)
}

// Reset the selection to a single range.
function setSimpleSelection (doc, anchor, head, options) {
  setSelection(doc, simpleSelection(anchor, head), options)
}

// Give beforeSelectionChange handlers a change to influence a
// selection update.
function filterSelectionChange (doc, sel, options) {
  var obj = {
    ranges: sel.ranges,
    update: function (ranges) {
      var this$1 = this

      this.ranges = []
      for (var i = 0; i < ranges.length; i++) {
        this$1.ranges[i] = new Range(clipPos(doc, ranges[i].anchor),
          clipPos(doc, ranges[i].head))
      }
    },
    origin: options && options.origin
  }
  signal(doc, 'beforeSelectionChange', doc, obj)
  if (doc.cm) {
    signal(doc.cm, 'beforeSelectionChange', doc.cm, obj)
  }
  if (obj.ranges != sel.ranges) {
    return normalizeSelection(doc.cm, obj.ranges, obj.ranges.length - 1)
  } else {
    return sel
  }
}

function setSelectionReplaceHistory (doc, sel, options) {
  var done = doc.history.done; var last = lst(done)
  if (last && last.ranges) {
    done[done.length - 1] = sel
    setSelectionNoUndo(doc, sel, options)
  } else {
    setSelection(doc, sel, options)
  }
}

// Set a new selection.
function setSelection (doc, sel, options) {
  setSelectionNoUndo(doc, sel, options)
  addSelectionToHistory(doc, doc.sel, doc.cm ? doc.cm.curOp.id : NaN, options)
}

function setSelectionNoUndo (doc, sel, options) {
  if (hasHandler(doc, 'beforeSelectionChange') || doc.cm && hasHandler(doc.cm, 'beforeSelectionChange')) {
    sel = filterSelectionChange(doc, sel, options)
  }

  var bias = options && options.bias ||
        (cmp(sel.primary().head, doc.sel.primary().head) < 0 ? -1 : 1)
  setSelectionInner(doc, skipAtomicInSelection(doc, sel, bias, true))

  if (!(options && options.scroll === false) && doc.cm) {
    ensureCursorVisible(doc.cm)
  }
}

function setSelectionInner (doc, sel) {
  if (sel.equals(doc.sel)) {
    return
  }

  doc.sel = sel

  if (doc.cm) {
    doc.cm.curOp.updateInput = 1
    doc.cm.curOp.selectionChanged = true
    signalCursorActivity(doc.cm)
  }
  signalLater(doc, 'cursorActivity', doc)
}

// Verify that the selection does not partially select any atomic
// index ranges.
function reCheckSelection (doc) {
  setSelectionInner(doc, skipAtomicInSelection(doc, doc.sel, null, false))
}

// Return a selection that does not partially select any atomic
// ranges.
function skipAtomicInSelection (doc, sel, bias, mayClear) {
  var out
  for (var i = 0; i < sel.ranges.length; i++) {
    var range = sel.ranges[i]
    var old = sel.ranges.length == doc.sel.ranges.length && doc.sel.ranges[i]
    var newAnchor = skipAtomic(doc, range.anchor, old && old.anchor, bias, mayClear)
    var newHead = skipAtomic(doc, range.head, old && old.head, bias, mayClear)
    if (out || newAnchor != range.anchor || newHead != range.head) {
      if (!out) {
        out = sel.ranges.slice(0, i)
      }
      out[i] = new Range(newAnchor, newHead)
    }
  }
  return out ? normalizeSelection(doc.cm, out, sel.primIndex) : sel
}

function skipAtomicInner (doc, pos, oldPos, dir, mayClear) {
  var line = getLine(doc, pos.line)
  if (line.markedSpans) {
    for (var i = 0; i < line.markedSpans.length; ++i) {
      var sp = line.markedSpans[i]; var m = sp.marker

      // Determine if we should prevent the cursor being placed to the left/right of an atomic marker
      // Historically this was determined using the inclusiveLeft/Right option, but the new way to control it
      // is with selectLeft/Right
      var preventCursorLeft = ('selectLeft' in m) ? !m.selectLeft : m.inclusiveLeft
      var preventCursorRight = ('selectRight' in m) ? !m.selectRight : m.inclusiveRight

      if ((sp.from == null || (preventCursorLeft ? sp.from <= pos.ch : sp.from < pos.ch)) &&
                (sp.to == null || (preventCursorRight ? sp.to >= pos.ch : sp.to > pos.ch))) {
        if (mayClear) {
          signal(m, 'beforeCursorEnter')
          if (m.explicitlyCleared) {
            if (!line.markedSpans) {
              break
            } else {
              --i
              continue
            }
          }
        }
        if (!m.atomic) {
          continue
        }

        if (oldPos) {
          var near = m.find(dir < 0 ? 1 : -1); var diff = (void 0)
          if (dir < 0 ? preventCursorRight : preventCursorLeft) {
            near = movePos(doc, near, -dir, near && near.line == pos.line ? line : null)
          }
          if (near && near.line == pos.line && (diff = cmp(near, oldPos)) && (dir < 0 ? diff < 0 : diff > 0)) {
            return skipAtomicInner(doc, near, pos, dir, mayClear)
          }
        }

        var far = m.find(dir < 0 ? -1 : 1)
        if (dir < 0 ? preventCursorLeft : preventCursorRight) {
          far = movePos(doc, far, dir, far.line == pos.line ? line : null)
        }
        return far ? skipAtomicInner(doc, far, pos, dir, mayClear) : null
      }
    }
  }
  return pos
}

// Ensure a given position is not inside an atomic range.
function skipAtomic (doc, pos, oldPos, bias, mayClear) {
  var dir = bias || 1
  var found = skipAtomicInner(doc, pos, oldPos, dir, mayClear) ||
        (!mayClear && skipAtomicInner(doc, pos, oldPos, dir, true)) ||
        skipAtomicInner(doc, pos, oldPos, -dir, mayClear) ||
        (!mayClear && skipAtomicInner(doc, pos, oldPos, -dir, true))
  if (!found) {
    doc.cantEdit = true
    return Pos(doc.first, 0)
  }
  return found
}

function movePos (doc, pos, dir, line) {
  if (dir < 0 && pos.ch == 0) {
    if (pos.line > doc.first) {
      return clipPos(doc, Pos(pos.line - 1))
    } else {
      return null
    }
  } else if (dir > 0 && pos.ch == (line || getLine(doc, pos.line)).text.length) {
    if (pos.line < doc.first + doc.size - 1) {
      return Pos(pos.line + 1, 0)
    } else {
      return null
    }
  } else {
    return new Pos(pos.line, pos.ch + dir)
  }
}

function selectAll (cm) {
  cm.setSelection(Pos(cm.firstLine(), 0), Pos(cm.lastLine()), sel_dontScroll)
}

// UPDATING

// Allow "beforeChange" event handlers to influence a change
function filterChange (doc, change, update) {
  var obj = {
    canceled: false,
    from: change.from,
    to: change.to,
    text: change.text,
    origin: change.origin,
    cancel: function () {
      return obj.canceled = true
    }
  }
  if (update) {
    obj.update = function (from, to, text, origin) {
      if (from) {
        obj.from = clipPos(doc, from)
      }
      if (to) {
        obj.to = clipPos(doc, to)
      }
      if (text) {
        obj.text = text
      }
      if (origin !== undefined) {
        obj.origin = origin
      }
    }
  }
  signal(doc, 'beforeChange', doc, obj)
  if (doc.cm) {
    signal(doc.cm, 'beforeChange', doc.cm, obj)
  }

  if (obj.canceled) {
    if (doc.cm) {
      doc.cm.curOp.updateInput = 2
    }
    return null
  }
  return { from: obj.from, to: obj.to, text: obj.text, origin: obj.origin }
}

// Apply a change to a document, and add it to the document's
// history, and propagating it to all linked documents.
function makeChange (doc, change, ignoreReadOnly) {
  if (doc.cm) {
    if (!doc.cm.curOp) {
      return operation(doc.cm, makeChange)(doc, change, ignoreReadOnly)
    }
    if (doc.cm.state.suppressEdits) {
      return
    }
  }

  if (hasHandler(doc, 'beforeChange') || doc.cm && hasHandler(doc.cm, 'beforeChange')) {
    change = filterChange(doc, change, true)
    if (!change) {
      return
    }
  }

  // Possibly split or suppress the update based on the presence
  // of read-only spans in its range.
  var split = sawReadOnlySpans && !ignoreReadOnly && removeReadOnlyRanges(doc, change.from, change.to)
  if (split) {
    for (var i = split.length - 1; i >= 0; --i) {
      makeChangeInner(doc, {
        from: split[i].from,
        to: split[i].to,
        text: i ? [''] : change.text,
        origin: change.origin
      })
    }
  } else {
    makeChangeInner(doc, change)
  }
}

function makeChangeInner (doc, change) {
  if (change.text.length == 1 && change.text[0] == '' && cmp(change.from, change.to) == 0) {
    return
  }
  var selAfter = computeSelAfterChange(doc, change)
  addChangeToHistory(doc, change, selAfter, doc.cm ? doc.cm.curOp.id : NaN)

  makeChangeSingleDoc(doc, change, selAfter, stretchSpansOverChange(doc, change))
  var rebased = []

  linkedDocs(doc, function (doc, sharedHist) {
    if (!sharedHist && indexOf(rebased, doc.history) == -1) {
      rebaseHist(doc.history, change)
      rebased.push(doc.history)
    }
    makeChangeSingleDoc(doc, change, null, stretchSpansOverChange(doc, change))
  })
}

// Revert a change stored in a document's history.
function makeChangeFromHistory (doc, type, allowSelectionOnly) {
  var suppress = doc.cm && doc.cm.state.suppressEdits
  if (suppress && !allowSelectionOnly) {
    return
  }

  var hist = doc.history; var event; var selAfter = doc.sel
  var source = type == 'undo' ? hist.done : hist.undone; var dest = type == 'undo' ? hist.undone : hist.done

  // Verify that there is a useable event (so that ctrl-z won't
  // needlessly clear selection events)
  var i = 0
  for (; i < source.length; i++) {
    event = source[i]
    if (allowSelectionOnly ? event.ranges && !event.equals(doc.sel) : !event.ranges) {
      break
    }
  }
  if (i == source.length) {
    return
  }
  hist.lastOrigin = hist.lastSelOrigin = null

  for (; ;) {
    event = source.pop()
    if (event.ranges) {
      pushSelectionToHistory(event, dest)
      if (allowSelectionOnly && !event.equals(doc.sel)) {
        setSelection(doc, event, { clearRedo: false })
        return
      }
      selAfter = event
    } else if (suppress) {
      source.push(event)
      return
    } else {
      break
    }
  }

  // Build up a reverse change object to add to the opposite history
  // stack (redo when undoing, and vice versa).
  var antiChanges = []
  pushSelectionToHistory(selAfter, dest)
  dest.push({ changes: antiChanges, generation: hist.generation })
  hist.generation = event.generation || ++hist.maxGeneration

  var filter = hasHandler(doc, 'beforeChange') || doc.cm && hasHandler(doc.cm, 'beforeChange')

  var loop = function (i) {
    var change = event.changes[i]
    change.origin = type
    if (filter && !filterChange(doc, change, false)) {
      source.length = 0
      return {}
    }

    antiChanges.push(historyChangeFromChange(doc, change))

    var after = i ? computeSelAfterChange(doc, change) : lst(source)
    makeChangeSingleDoc(doc, change, after, mergeOldSpans(doc, change))
    if (!i && doc.cm) {
      doc.cm.scrollIntoView({ from: change.from, to: changeEnd(change) })
    }
    var rebased = []

    // Propagate to the linked documents
    linkedDocs(doc, function (doc, sharedHist) {
      if (!sharedHist && indexOf(rebased, doc.history) == -1) {
        rebaseHist(doc.history, change)
        rebased.push(doc.history)
      }
      makeChangeSingleDoc(doc, change, null, mergeOldSpans(doc, change))
    })
  }

  for (var i$1 = event.changes.length - 1; i$1 >= 0; --i$1) {
    var returned = loop(i$1)

    if (returned) return returned.v
  }
}

// Sub-views need their line numbers shifted when text is added
// above or below them in the parent document.
function shiftDoc (doc, distance) {
  if (distance == 0) {
    return
  }
  doc.first += distance
  doc.sel = new Selection(map(doc.sel.ranges, function (range) {
    return new Range(
      Pos(range.anchor.line + distance, range.anchor.ch),
      Pos(range.head.line + distance, range.head.ch)
    )
  }), doc.sel.primIndex)
  if (doc.cm) {
    regChange(doc.cm, doc.first, doc.first - distance, distance)
    for (var d = doc.cm.display, l = d.viewFrom; l < d.viewTo; l++) {
      regLineChange(doc.cm, l, 'gutter')
    }
  }
}

// More lower-level change function, handling only a single document
// (not linked ones).
function makeChangeSingleDoc (doc, change, selAfter, spans) {
  if (doc.cm && !doc.cm.curOp) {
    return operation(doc.cm, makeChangeSingleDoc)(doc, change, selAfter, spans)
  }

  if (change.to.line < doc.first) {
    shiftDoc(doc, change.text.length - 1 - (change.to.line - change.from.line))
    return
  }
  if (change.from.line > doc.lastLine()) {
    return
  }

  // Clip the change to the size of this docs
  if (change.from.line < doc.first) {
    var shift = change.text.length - 1 - (doc.first - change.from.line)
    shiftDoc(doc, shift)
    change = {
      from: Pos(doc.first, 0),
      to: Pos(change.to.line + shift, change.to.ch),
      text: [lst(change.text)],
      origin: change.origin
    }
  }
  var last = doc.lastLine()
  if (change.to.line > last) {
    change = {
      from: change.from,
      to: Pos(last, getLine(doc, last).text.length),
      text: [change.text[0]],
      origin: change.origin
    }
  }

  change.removed = getBetween(doc, change.from, change.to)

  if (!selAfter) {
    selAfter = computeSelAfterChange(doc, change)
  }
  if (doc.cm) {
    makeChangeSingleDocInEditor(doc.cm, change, spans)
  } else {
    updateDoc(doc, change, spans)
  }
  setSelectionNoUndo(doc, selAfter, sel_dontScroll)

  if (doc.cantEdit && skipAtomic(doc, Pos(doc.firstLine(), 0))) {
    doc.cantEdit = false
  }
}

// Handle the interaction of a change to a document with the src
// that this document is part of.
function makeChangeSingleDocInEditor (cm, change, spans) {
  var doc = cm.doc; var display = cm.display; var from = change.from; var to = change.to

  var recomputeMaxLength = false; var checkWidthStart = from.line
  if (!cm.options.lineWrapping) {
    checkWidthStart = lineNo(visualLine(getLine(doc, from.line)))
    doc.iter(checkWidthStart, to.line + 1, function (line) {
      if (line == display.maxLine) {
        recomputeMaxLength = true
        return true
      }
    })
  }

  if (doc.sel.contains(change.from, change.to) > -1) {
    signalCursorActivity(cm)
  }

  updateDoc(doc, change, spans, estimateHeight(cm))

  if (!cm.options.lineWrapping) {
    doc.iter(checkWidthStart, from.line + change.text.length, function (line) {
      var len = lineLength(line)
      if (len > display.maxLineLength) {
        display.maxLine = line
        display.maxLineLength = len
        display.maxLineChanged = true
        recomputeMaxLength = false
      }
    })
    if (recomputeMaxLength) {
      cm.curOp.updateMaxLine = true
    }
  }

  retreatFrontier(doc, from.line)
  startWorker(cm, 400)

  var lendiff = change.text.length - (to.line - from.line) - 1
  // Remember that these lines changed, for updating the display
  if (change.full) {
    regChange(cm)
  } else if (from.line == to.line && change.text.length == 1 && !isWholeLineUpdate(cm.doc, change)) {
    regLineChange(cm, from.line, 'text')
  } else {
    regChange(cm, from.line, to.line + 1, lendiff)
  }

  var changesHandler = hasHandler(cm, 'changes'); var changeHandler = hasHandler(cm, 'change')
  if (changeHandler || changesHandler) {
    var obj = {
      from: from,
      to: to,
      text: change.text,
      removed: change.removed,
      origin: change.origin
    }
    if (changeHandler) {
      signalLater(cm, 'change', cm, obj)
    }
    if (changesHandler) {
      (cm.curOp.changeObjs || (cm.curOp.changeObjs = [])).push(obj)
    }
  }
  cm.display.selForContextMenu = null
}

function replaceRange (doc, code, from, to, origin) {
  var assign

  if (!to) {
    to = from
  }
  if (cmp(to, from) < 0) {
    (assign = [to, from], from = assign[0], to = assign[1])
  }
  if (typeof code === 'string') {
    code = doc.splitLines(code)
  }
  makeChange(doc, { from: from, to: to, text: code, origin: origin })
}

// Rebasing/resetting history to deal with externally-sourced changes

function rebaseHistSelSingle (pos, from, to, diff) {
  if (to < pos.line) {
    pos.line += diff
  } else if (from < pos.line) {
    pos.line = from
    pos.ch = 0
  }
}

// Tries to rebase an array of history events given a change in the
// document. If the change touches the same lines as the event, the
// event, and everything 'behind' it, is discarded. If the change is
// before the event, the event's positions are updated. Uses a
// copy-on-write scheme for the positions, to avoid having to
// reallocate them all on every rebase, but also avoid problems with
// shared position objects being unsafely updated.
function rebaseHistArray (array, from, to, diff) {
  for (var i = 0; i < array.length; ++i) {
    var sub = array[i]; var ok = true
    if (sub.ranges) {
      if (!sub.copied) {
        sub = array[i] = sub.deepCopy()
        sub.copied = true
      }
      for (var j = 0; j < sub.ranges.length; j++) {
        rebaseHistSelSingle(sub.ranges[j].anchor, from, to, diff)
        rebaseHistSelSingle(sub.ranges[j].head, from, to, diff)
      }
      continue
    }
    for (var j$1 = 0; j$1 < sub.changes.length; ++j$1) {
      var cur = sub.changes[j$1]
      if (to < cur.from.line) {
        cur.from = Pos(cur.from.line + diff, cur.from.ch)
        cur.to = Pos(cur.to.line + diff, cur.to.ch)
      } else if (from <= cur.to.line) {
        ok = false
        break
      }
    }
    if (!ok) {
      array.splice(0, i + 1)
      i = 0
    }
  }
}

function rebaseHist (hist, change) {
  var from = change.from.line; var to = change.to.line; var diff = change.text.length - (to - from) - 1
  rebaseHistArray(hist.done, from, to, diff)
  rebaseHistArray(hist.undone, from, to, diff)
}

// Utility for applying a change to a line by handle or number,
// returning the number and optionally registering the line as
// changed.
function changeLine (doc, handle, changeType, op) {
  var no = handle; var line = handle
  if (typeof handle === 'number') {
    line = getLine(doc, clipLine(doc, handle))
  } else {
    no = lineNo(handle)
  }
  if (no == null) {
    return null
  }
  if (op(line, no) && doc.cm) {
    regLineChange(doc.cm, no, changeType)
  }
  return line
}

// The document is represented as a BTree consisting of leaves, with
// chunk of lines in them, and branches, with up to ten leaves or
// other branch nodes below them. The top node is always a branch
// node, and is the document object itself (meaning it has
// additional methods and properties).
//
// All nodes have parent links. The tree is used both to go from
// line numbers to line objects, and to go from objects to numbers.
// It also indexes by height, and is used to convert between height
// and line object, and to find the total height of the document.
//
// See also http://marijnhaverbeke.nl/blog/codemirror-line-tree.html

function LeafChunk (lines) {
  var this$1 = this

  this.lines = lines
  this.parent = null
  var height = 0
  for (var i = 0; i < lines.length; ++i) {
    lines[i].parent = this$1
    height += lines[i].height
  }
  this.height = height
}

LeafChunk.prototype = {
  chunkSize: function () {
    return this.lines.length
  },

  // Remove the n lines at offset 'at'.
  removeInner: function (at, n) {
    var this$1 = this

    for (var i = at, e = at + n; i < e; ++i) {
      var line = this$1.lines[i]
      this$1.height -= line.height
      cleanUpLine(line)
      signalLater(line, 'delete')
    }
    this.lines.splice(at, n)
  },

  // Helper used to collapse a small branch into a single leaf.
  collapse: function (lines) {
    lines.push.apply(lines, this.lines)
  },

  // Insert the given array of lines at offset 'at', count them as
  // having the given height.
  insertInner: function (at, lines, height) {
    var this$1 = this

    this.height += height
    this.lines = this.lines.slice(0, at).concat(lines).concat(this.lines.slice(at))
    for (var i = 0; i < lines.length; ++i) {
      lines[i].parent = this$1
    }
  },

  // Used to iterate over a part of the tree.
  iterN: function (at, n, op) {
    var this$1 = this

    for (var e = at + n; at < e; ++at) {
      if (op(this$1.lines[at])) {
        return true
      }
    }
  }
}

function BranchChunk (children) {
  var this$1 = this

  this.children = children
  var size = 0; var height = 0
  for (var i = 0; i < children.length; ++i) {
    var ch = children[i]
    size += ch.chunkSize()
    height += ch.height
    ch.parent = this$1
  }
  this.size = size
  this.height = height
  this.parent = null
}

BranchChunk.prototype = {
  chunkSize: function () {
    return this.size
  },

  removeInner: function (at, n) {
    var this$1 = this

    this.size -= n
    for (var i = 0; i < this.children.length; ++i) {
      var child = this$1.children[i]; var sz = child.chunkSize()
      if (at < sz) {
        var rm = Math.min(n, sz - at); var oldHeight = child.height
        child.removeInner(at, rm)
        this$1.height -= oldHeight - child.height
        if (sz == rm) {
          this$1.children.splice(i--, 1)
          child.parent = null
        }
        if ((n -= rm) == 0) {
          break
        }
        at = 0
      } else {
        at -= sz
      }
    }
    // If the result is smaller than 25 lines, ensure that it is a
    // single leaf node.
    if (this.size - n < 25 &&
            (this.children.length > 1 || !(this.children[0] instanceof LeafChunk))) {
      var lines = []
      this.collapse(lines)
      this.children = [new LeafChunk(lines)]
      this.children[0].parent = this
    }
  },

  collapse: function (lines) {
    var this$1 = this

    for (var i = 0; i < this.children.length; ++i) {
      this$1.children[i].collapse(lines)
    }
  },

  insertInner: function (at, lines, height) {
    var this$1 = this

    this.size += lines.length
    this.height += height
    for (var i = 0; i < this.children.length; ++i) {
      var child = this$1.children[i]; var sz = child.chunkSize()
      if (at <= sz) {
        child.insertInner(at, lines, height)
        if (child.lines && child.lines.length > 50) {
          // To avoid memory thrashing when child.lines is huge (e.g. first view of a large file), it's never spliced.
          // Instead, small slices are taken. They're taken in order because sequential memory accesses are fastest.
          var remaining = child.lines.length % 25 + 25
          for (var pos = remaining; pos < child.lines.length;) {
            var leaf = new LeafChunk(child.lines.slice(pos, pos += 25))
            child.height -= leaf.height
            this$1.children.splice(++i, 0, leaf)
            leaf.parent = this$1
          }
          child.lines = child.lines.slice(0, remaining)
          this$1.maybeSpill()
        }
        break
      }
      at -= sz
    }
  },

  // When a node has grown, check whether it should be split.
  maybeSpill: function () {
    if (this.children.length <= 10) {
      return
    }
    var me = this
    do {
      var spilled = me.children.splice(me.children.length - 5, 5)
      var sibling = new BranchChunk(spilled)
      if (!me.parent) { // Become the parent node
        var copy = new BranchChunk(me.children)
        copy.parent = me
        me.children = [copy, sibling]
        me = copy
      } else {
        me.size -= sibling.size
        me.height -= sibling.height
        var myIndex = indexOf(me.parent.children, me)
        me.parent.children.splice(myIndex + 1, 0, sibling)
      }
      sibling.parent = me.parent
    } while (me.children.length > 10)
    me.parent.maybeSpill()
  },

  iterN: function (at, n, op) {
    var this$1 = this

    for (var i = 0; i < this.children.length; ++i) {
      var child = this$1.children[i]; var sz = child.chunkSize()
      if (at < sz) {
        var used = Math.min(n, sz - at)
        if (child.iterN(at, used, op)) {
          return true
        }
        if ((n -= used) == 0) {
          break
        }
        at = 0
      } else {
        at -= sz
      }
    }
  }
}

// Line widgets are block elements displayed above or below a line.

var LineWidget = function (doc, node, options) {
  var this$1 = this

  if (options) {
    for (var opt in options) {
      if (options.hasOwnProperty(opt)) {
        this$1[opt] = options[opt]
      }
    }
  }
  this.doc = doc
  this.node = node
}

LineWidget.prototype.clear = function () {
  var this$1 = this

  var cm = this.doc.cm; var ws = this.line.widgets; var line = this.line; var no = lineNo(line)
  if (no == null || !ws) {
    return
  }
  for (var i = 0; i < ws.length; ++i) {
    if (ws[i] == this$1) {
      ws.splice(i--, 1)
    }
  }
  if (!ws.length) {
    line.widgets = null
  }
  var height = widgetHeight(this)
  updateLineHeight(line, Math.max(0, line.height - height))
  if (cm) {
    runInOp(cm, function () {
      adjustScrollWhenAboveVisible(cm, line, -height)
      regLineChange(cm, no, 'widget')
    })
    signalLater(cm, 'lineWidgetCleared', cm, this, no)
  }
}

LineWidget.prototype.changed = function () {
  var this$1 = this

  var oldH = this.height; var cm = this.doc.cm; var line = this.line
  this.height = null
  var diff = widgetHeight(this) - oldH
  if (!diff) {
    return
  }
  if (!lineIsHidden(this.doc, line)) {
    updateLineHeight(line, line.height + diff)
  }
  if (cm) {
    runInOp(cm, function () {
      cm.curOp.forceUpdate = true
      adjustScrollWhenAboveVisible(cm, line, diff)
      signalLater(cm, 'lineWidgetChanged', cm, this$1, lineNo(line))
    })
  }
}
eventMixin(LineWidget)

function adjustScrollWhenAboveVisible (cm, line, diff) {
  if (heightAtLine(line) < ((cm.curOp && cm.curOp.scrollTop) || cm.doc.scrollTop)) {
    addToScrollTop(cm, diff)
  }
}

function addLineWidget (doc, handle, node, options) {
  var widget = new LineWidget(doc, node, options)
  var cm = doc.cm
  if (cm && widget.noHScroll) {
    cm.display.alignWidgets = true
  }
  changeLine(doc, handle, 'widget', function (line) {
    var widgets = line.widgets || (line.widgets = [])
    if (widget.insertAt == null) {
      widgets.push(widget)
    } else {
      widgets.splice(Math.min(widgets.length - 1, Math.max(0, widget.insertAt)), 0, widget)
    }
    widget.line = line
    if (cm && !lineIsHidden(doc, line)) {
      var aboveVisible = heightAtLine(line) < doc.scrollTop
      updateLineHeight(line, line.height + widgetHeight(widget))
      if (aboveVisible) {
        addToScrollTop(cm, widget.height)
      }
      cm.curOp.forceUpdate = true
    }
    return true
  })
  if (cm) {
    signalLater(cm, 'lineWidgetAdded', cm, widget, typeof handle === 'number' ? handle : lineNo(handle))
  }
  return widget
}

var nextMarkerId = 0

var TextMarker = function (doc, type) {
  this.lines = []
  this.type = type
  this.doc = doc
  this.id = ++nextMarkerId
}

// Clear the marker.
TextMarker.prototype.clear = function () {
  var this$1 = this

  if (this.explicitlyCleared) {
    return
  }
  var cm = this.doc.cm; var withOp = cm && !cm.curOp
  if (withOp) {
    startOperation(cm)
  }
  if (hasHandler(this, 'clear')) {
    var found = this.find()
    if (found) {
      signalLater(this, 'clear', found.from, found.to)
    }
  }
  var min = null; var max = null
  for (var i = 0; i < this.lines.length; ++i) {
    var line = this$1.lines[i]
    var span = getMarkedSpanFor(line.markedSpans, this$1)
    if (cm && !this$1.collapsed) {
      regLineChange(cm, lineNo(line), 'text')
    } else if (cm) {
      if (span.to != null) {
        max = lineNo(line)
      }
      if (span.from != null) {
        min = lineNo(line)
      }
    }
    line.markedSpans = removeMarkedSpan(line.markedSpans, span)
    if (span.from == null && this$1.collapsed && !lineIsHidden(this$1.doc, line) && cm) {
      updateLineHeight(line, textHeight(cm.display))
    }
  }
  if (cm && this.collapsed && !cm.options.lineWrapping) {
    for (var i$1 = 0; i$1 < this.lines.length; ++i$1) {
      var visual = visualLine(this$1.lines[i$1]); var len = lineLength(visual)
      if (len > cm.display.maxLineLength) {
        cm.display.maxLine = visual
        cm.display.maxLineLength = len
        cm.display.maxLineChanged = true
      }
    }
  }

  if (min != null && cm && this.collapsed) {
    regChange(cm, min, max + 1)
  }
  this.lines.length = 0
  this.explicitlyCleared = true
  if (this.atomic && this.doc.cantEdit) {
    this.doc.cantEdit = false
    if (cm) {
      reCheckSelection(cm.doc)
    }
  }
  if (cm) {
    signalLater(cm, 'markerCleared', cm, this, min, max)
  }
  if (withOp) {
    endOperation(cm)
  }
  if (this.parent) {
    this.parent.clear()
  }
}

// Find the position of the marker in the document. Returns a {from,
// to} object by default. Side can be passed to get a specific side
// -- 0 (both), -1 (left), or 1 (right). When lineObj is true, the
// Pos objects returned contain a line object, rather than a line
// number (used to prevent looking up the same line twice).
TextMarker.prototype.find = function (side, lineObj) {
  var this$1 = this

  if (side == null && this.type == 'bookmark') {
    side = 1
  }
  var from, to
  for (var i = 0; i < this.lines.length; ++i) {
    var line = this$1.lines[i]
    var span = getMarkedSpanFor(line.markedSpans, this$1)
    if (span.from != null) {
      from = Pos(lineObj ? line : lineNo(line), span.from)
      if (side == -1) {
        return from
      }
    }
    if (span.to != null) {
      to = Pos(lineObj ? line : lineNo(line), span.to)
      if (side == 1) {
        return to
      }
    }
  }
  return from && { from: from, to: to }
}

// Signals that the marker's widget changed, and surrounding layout
// should be recomputed.
TextMarker.prototype.changed = function () {
  var this$1 = this

  var pos = this.find(-1, true); var widget = this; var cm = this.doc.cm
  if (!pos || !cm) {
    return
  }
  runInOp(cm, function () {
    var line = pos.line; var lineN = lineNo(pos.line)
    var view = findViewForLine(cm, lineN)
    if (view) {
      clearLineMeasurementCacheFor(view)
      cm.curOp.selectionChanged = cm.curOp.forceUpdate = true
    }
    cm.curOp.updateMaxLine = true
    if (!lineIsHidden(widget.doc, line) && widget.height != null) {
      var oldHeight = widget.height
      widget.height = null
      var dHeight = widgetHeight(widget) - oldHeight
      if (dHeight) {
        updateLineHeight(line, line.height + dHeight)
      }
    }
    signalLater(cm, 'markerChanged', cm, this$1)
  })
}

TextMarker.prototype.attachLine = function (line) {
  if (!this.lines.length && this.doc.cm) {
    var op = this.doc.cm.curOp
    if (!op.maybeHiddenMarkers || indexOf(op.maybeHiddenMarkers, this) == -1) {
      (op.maybeUnhiddenMarkers || (op.maybeUnhiddenMarkers = [])).push(this)
    }
  }
  this.lines.push(line)
}

TextMarker.prototype.detachLine = function (line) {
  this.lines.splice(indexOf(this.lines, line), 1)
  if (!this.lines.length && this.doc.cm) {
    var op = this.doc.cm.curOp
        ;(op.maybeHiddenMarkers || (op.maybeHiddenMarkers = [])).push(this)
  }
}
eventMixin(TextMarker)

// Create a marker, wire it up to the right lines, and
function markText (doc, from, to, options, type) {
  // Shared markers (across linked documents) are handled separately
  // (markTextShared will call out to this again, once per
  // document).
  if (options && options.shared) {
    return markTextShared(doc, from, to, options, type)
  }
  // Ensure we are in an operation.
  if (doc.cm && !doc.cm.curOp) {
    return operation(doc.cm, markText)(doc, from, to, options, type)
  }

  var marker = new TextMarker(doc, type); var diff = cmp(from, to)
  if (options) {
    copyObj(options, marker, false)
  }
  // Don't connect empty markers unless clearWhenEmpty is false
  if (diff > 0 || diff == 0 && marker.clearWhenEmpty !== false) {
    return marker
  }
  if (marker.replacedWith) {
    // Showing up as a widget implies collapsed (widget replaces text)
    marker.collapsed = true
    marker.widgetNode = eltP('span', [marker.replacedWith], 'CodeMirror-widget')
    if (!options.handleMouseEvents) {
      marker.widgetNode.setAttribute('cm-ignore-events', 'true')
    }
    if (options.insertLeft) {
      marker.widgetNode.insertLeft = true
    }
  }
  if (marker.collapsed) {
    if (conflictingCollapsedRange(doc, from.line, from, to, marker) ||
            from.line != to.line && conflictingCollapsedRange(doc, to.line, from, to, marker)) {
      throw new Error('Inserting collapsed marker partially overlapping an existing one')
    }
    seeCollapsedSpans()
  }

  if (marker.addToHistory) {
    addChangeToHistory(doc, { from: from, to: to, origin: 'markText' }, doc.sel, NaN)
  }

  var curLine = from.line; var cm = doc.cm; var updateMaxLine
  doc.iter(curLine, to.line + 1, function (line) {
    if (cm && marker.collapsed && !cm.options.lineWrapping && visualLine(line) == cm.display.maxLine) {
      updateMaxLine = true
    }
    if (marker.collapsed && curLine != from.line) {
      updateLineHeight(line, 0)
    }
    addMarkedSpan(line, new MarkedSpan(marker,
      curLine == from.line ? from.ch : null,
      curLine == to.line ? to.ch : null))
    ++curLine
  })
  // lineIsHidden depends on the presence of the spans, so needs a second pass
  if (marker.collapsed) {
    doc.iter(from.line, to.line + 1, function (line) {
      if (lineIsHidden(doc, line)) {
        updateLineHeight(line, 0)
      }
    })
  }

  if (marker.clearOnEnter) {
    on(marker, 'beforeCursorEnter', function () {
      return marker.clear()
    })
  }

  if (marker.readOnly) {
    seeReadOnlySpans()
    if (doc.history.done.length || doc.history.undone.length) {
      doc.clearHistory()
    }
  }
  if (marker.collapsed) {
    marker.id = ++nextMarkerId
    marker.atomic = true
  }
  if (cm) {
    // Sync src state
    if (updateMaxLine) {
      cm.curOp.updateMaxLine = true
    }
    if (marker.collapsed) {
      regChange(cm, from.line, to.line + 1)
    } else if (marker.className || marker.startStyle || marker.endStyle || marker.css ||
            marker.attributes || marker.title) {
      for (var i = from.line; i <= to.line; i++) {
        regLineChange(cm, i, 'text')
      }
    }
    if (marker.atomic) {
      reCheckSelection(cm.doc)
    }
    signalLater(cm, 'markerAdded', cm, marker)
  }
  return marker
}

// SHARED TEXTMARKERS

// A shared marker spans multiple linked documents. It is
// implemented as a meta-marker-object controlling multiple normal
// markers.
var SharedTextMarker = function (markers, primary) {
  var this$1 = this

  this.markers = markers
  this.primary = primary
  for (var i = 0; i < markers.length; ++i) {
    markers[i].parent = this$1
  }
}

SharedTextMarker.prototype.clear = function () {
  var this$1 = this

  if (this.explicitlyCleared) {
    return
  }
  this.explicitlyCleared = true
  for (var i = 0; i < this.markers.length; ++i) {
    this$1.markers[i].clear()
  }
  signalLater(this, 'clear')
}

SharedTextMarker.prototype.find = function (side, lineObj) {
  return this.primary.find(side, lineObj)
}
eventMixin(SharedTextMarker)

function markTextShared (doc, from, to, options, type) {
  options = copyObj(options)
  options.shared = false
  var markers = [markText(doc, from, to, options, type)]; var primary = markers[0]
  var widget = options.widgetNode
  linkedDocs(doc, function (doc) {
    if (widget) {
      options.widgetNode = widget.cloneNode(true)
    }
    markers.push(markText(doc, clipPos(doc, from), clipPos(doc, to), options, type))
    for (var i = 0; i < doc.linked.length; ++i) {
      if (doc.linked[i].isParent) {
        return
      }
    }
    primary = lst(markers)
  })
  return new SharedTextMarker(markers, primary)
}

function findSharedMarkers (doc) {
  return doc.findMarks(Pos(doc.first, 0), doc.clipPos(Pos(doc.lastLine())), function (m) {
    return m.parent
  })
}

function copySharedMarkers (doc, markers) {
  for (var i = 0; i < markers.length; i++) {
    var marker = markers[i]; var pos = marker.find()
    var mFrom = doc.clipPos(pos.from); var mTo = doc.clipPos(pos.to)
    if (cmp(mFrom, mTo)) {
      var subMark = markText(doc, mFrom, mTo, marker.primary, marker.primary.type)
      marker.markers.push(subMark)
      subMark.parent = marker
    }
  }
}

function detachSharedMarkers (markers) {
  var loop = function (i) {
    var marker = markers[i]; var linked = [marker.primary.doc]
    linkedDocs(marker.primary.doc, function (d) {
      return linked.push(d)
    })
    for (var j = 0; j < marker.markers.length; j++) {
      var subMarker = marker.markers[j]
      if (indexOf(linked, subMarker.doc) == -1) {
        subMarker.parent = null
        marker.markers.splice(j--, 1)
      }
    }
  }

  for (var i = 0; i < markers.length; i++) loop(i)
}

var nextDocId = 0
var Doc = function (text, mode, firstLine, lineSep, direction) {
  if (!(this instanceof Doc)) {
    return new Doc(text, mode, firstLine, lineSep, direction)
  }
  if (firstLine == null) {
    firstLine = 0
  }

  BranchChunk.call(this, [new LeafChunk([new Line('', null)])])
  this.first = firstLine
  this.scrollTop = this.scrollLeft = 0
  this.cantEdit = false
  this.cleanGeneration = 1
  this.modeFrontier = this.highlightFrontier = firstLine
  var start = Pos(firstLine, 0)
  this.sel = simpleSelection(start)
  this.history = new History(null)
  this.id = ++nextDocId
  this.modeOption = mode
  this.lineSep = lineSep
  this.direction = (direction == 'rtl') ? 'rtl' : 'ltr'
  this.extend = false

  if (typeof text === 'string') {
    text = this.splitLines(text)
  }
  updateDoc(this, { from: start, to: start, text: text })
  setSelection(this, simpleSelection(start), sel_dontScroll)
}

Doc.prototype = createObj(BranchChunk.prototype, {
  constructor: Doc,
  // Iterate over the document. Supports two forms -- with only one
  // argument, it calls that for each line in the document. With
  // three, it iterates over the range given by the first two (with
  // the second being non-inclusive).
  iter: function (from, to, op) {
    if (op) {
      this.iterN(from - this.first, to - from, op)
    } else {
      this.iterN(this.first, this.first + this.size, from)
    }
  },

  // Non-public interface for adding and removing lines.
  insert: function (at, lines) {
    var height = 0
    for (var i = 0; i < lines.length; ++i) {
      height += lines[i].height
    }
    this.insertInner(at - this.first, lines, height)
  },
  remove: function (at, n) {
    this.removeInner(at - this.first, n)
  },
  getValue: function (lineSep) {
    var lines = getLines(this, this.first, this.first + this.size)
    if (lineSep === false) {
      return lines
    }
    return lines.join(lineSep || this.lineSeparator())
  },
  setValue: docMethodOp(function (code) {
    var top = Pos(this.first, 0); var last = this.first + this.size - 1
    makeChange(this, {
      from: top,
      to: Pos(last, getLine(this, last).text.length),
      text: this.splitLines(code),
      origin: 'setValue',
      full: true
    }, true)
    if (this.cm) {
      scrollToCoords(this.cm, 0, 0)
    }
    setSelection(this, simpleSelection(top), sel_dontScroll)
  }),
  replaceRange: function (code, from, to, origin) {
    from = clipPos(this, from)
    to = to ? clipPos(this, to) : from
    replaceRange(this, code, from, to, origin)
  },
  getRange: function (from, to, lineSep) {
    var lines = getBetween(this, clipPos(this, from), clipPos(this, to))
    if (lineSep === false) {
      return lines
    }
    return lines.join(lineSep || this.lineSeparator())
  },

  getLine: function (line) {
    var l = this.getLineHandle(line)
    return l && l.text
  },

  getLineHandle: function (line) {
    if (isLine(this, line)) {
      return getLine(this, line)
    }
  },
  getLineNumber: function (line) {
    return lineNo(line)
  },

  getLineHandleVisualStart: function (line) {
    if (typeof line === 'number') {
      line = getLine(this, line)
    }
    return visualLine(line)
  },

  lineCount: function () {
    return this.size
  },
  firstLine: function () {
    return this.first
  },
  lastLine: function () {
    return this.first + this.size - 1
  },

  clipPos: function (pos) {
    return clipPos(this, pos)
  },

  getCursor: function (start) {
    var range$$1 = this.sel.primary(); var pos
    if (start == null || start == 'head') {
      pos = range$$1.head
    } else if (start == 'anchor') {
      pos = range$$1.anchor
    } else if (start == 'end' || start == 'to' || start === false) {
      pos = range$$1.to()
    } else {
      pos = range$$1.from()
    }
    return pos
  },
  listSelections: function () {
    return this.sel.ranges
  },
  somethingSelected: function () {
    return this.sel.somethingSelected()
  },

  setCursor: docMethodOp(function (line, ch, options) {
    setSimpleSelection(this, clipPos(this, typeof line === 'number' ? Pos(line, ch || 0) : line), null, options)
  }),
  setSelection: docMethodOp(function (anchor, head, options) {
    setSimpleSelection(this, clipPos(this, anchor), clipPos(this, head || anchor), options)
  }),
  extendSelection: docMethodOp(function (head, other, options) {
    extendSelection(this, clipPos(this, head), other && clipPos(this, other), options)
  }),
  extendSelections: docMethodOp(function (heads, options) {
    extendSelections(this, clipPosArray(this, heads), options)
  }),
  extendSelectionsBy: docMethodOp(function (f, options) {
    var heads = map(this.sel.ranges, f)
    extendSelections(this, clipPosArray(this, heads), options)
  }),
  setSelections: docMethodOp(function (ranges, primary, options) {
    var this$1 = this

    if (!ranges.length) {
      return
    }
    var out = []
    for (var i = 0; i < ranges.length; i++) {
      out[i] = new Range(clipPos(this$1, ranges[i].anchor),
        clipPos(this$1, ranges[i].head))
    }
    if (primary == null) {
      primary = Math.min(ranges.length - 1, this.sel.primIndex)
    }
    setSelection(this, normalizeSelection(this.cm, out, primary), options)
  }),
  addSelection: docMethodOp(function (anchor, head, options) {
    var ranges = this.sel.ranges.slice(0)
    ranges.push(new Range(clipPos(this, anchor), clipPos(this, head || anchor)))
    setSelection(this, normalizeSelection(this.cm, ranges, ranges.length - 1), options)
  }),

  getSelection: function (lineSep) {
    var this$1 = this

    var ranges = this.sel.ranges; var lines
    for (var i = 0; i < ranges.length; i++) {
      var sel = getBetween(this$1, ranges[i].from(), ranges[i].to())
      lines = lines ? lines.concat(sel) : sel
    }
    if (lineSep === false) {
      return lines
    } else {
      return lines.join(lineSep || this.lineSeparator())
    }
  },
  getSelections: function (lineSep) {
    var this$1 = this

    var parts = []; var ranges = this.sel.ranges
    for (var i = 0; i < ranges.length; i++) {
      var sel = getBetween(this$1, ranges[i].from(), ranges[i].to())
      if (lineSep !== false) {
        sel = sel.join(lineSep || this$1.lineSeparator())
      }
      parts[i] = sel
    }
    return parts
  },
  replaceSelection: function (code, collapse, origin) {
    var dup = []
    for (var i = 0; i < this.sel.ranges.length; i++) {
      dup[i] = code
    }
    this.replaceSelections(dup, collapse, origin || '+input')
  },
  replaceSelections: docMethodOp(function (code, collapse, origin) {
    var this$1 = this

    var changes = []; var sel = this.sel
    for (var i = 0; i < sel.ranges.length; i++) {
      var range$$1 = sel.ranges[i]
      changes[i] = { from: range$$1.from(), to: range$$1.to(), text: this$1.splitLines(code[i]), origin: origin }
    }
    var newSel = collapse && collapse != 'end' && computeReplacedSel(this, changes, collapse)
    for (var i$1 = changes.length - 1; i$1 >= 0; i$1--) {
      makeChange(this$1, changes[i$1])
    }
    if (newSel) {
      setSelectionReplaceHistory(this, newSel)
    } else if (this.cm) {
      ensureCursorVisible(this.cm)
    }
  }),
  undo: docMethodOp(function () {
    makeChangeFromHistory(this, 'undo')
  }),
  redo: docMethodOp(function () {
    makeChangeFromHistory(this, 'redo')
  }),
  undoSelection: docMethodOp(function () {
    makeChangeFromHistory(this, 'undo', true)
  }),
  redoSelection: docMethodOp(function () {
    makeChangeFromHistory(this, 'redo', true)
  }),

  setExtending: function (val) {
    this.extend = val
  },
  getExtending: function () {
    return this.extend
  },

  historySize: function () {
    var hist = this.history; var done = 0; var undone = 0
    for (var i = 0; i < hist.done.length; i++) {
      if (!hist.done[i].ranges) {
        ++done
      }
    }
    for (var i$1 = 0; i$1 < hist.undone.length; i$1++) {
      if (!hist.undone[i$1].ranges) {
        ++undone
      }
    }
    return { undo: done, redo: undone }
  },
  clearHistory: function () {
    this.history = new History(this.history.maxGeneration)
  },

  markClean: function () {
    this.cleanGeneration = this.changeGeneration(true)
  },
  changeGeneration: function (forceSplit) {
    if (forceSplit) {
      this.history.lastOp = this.history.lastSelOp = this.history.lastOrigin = null
    }
    return this.history.generation
  },
  isClean: function (gen) {
    return this.history.generation == (gen || this.cleanGeneration)
  },

  getHistory: function () {
    return {
      done: copyHistoryArray(this.history.done),
      undone: copyHistoryArray(this.history.undone)
    }
  },
  setHistory: function (histData) {
    var hist = this.history = new History(this.history.maxGeneration)
    hist.done = copyHistoryArray(histData.done.slice(0), null, true)
    hist.undone = copyHistoryArray(histData.undone.slice(0), null, true)
  },

  setGutterMarker: docMethodOp(function (line, gutterID, value) {
    return changeLine(this, line, 'gutter', function (line) {
      var markers = line.gutterMarkers || (line.gutterMarkers = {})
      markers[gutterID] = value
      if (!value && isEmpty(markers)) {
        line.gutterMarkers = null
      }
      return true
    })
  }),

  clearGutter: docMethodOp(function (gutterID) {
    var this$1 = this

    this.iter(function (line) {
      if (line.gutterMarkers && line.gutterMarkers[gutterID]) {
        changeLine(this$1, line, 'gutter', function () {
          line.gutterMarkers[gutterID] = null
          if (isEmpty(line.gutterMarkers)) {
            line.gutterMarkers = null
          }
          return true
        })
      }
    })
  }),

  lineInfo: function (line) {
    var n
    if (typeof line === 'number') {
      if (!isLine(this, line)) {
        return null
      }
      n = line
      line = getLine(this, line)
      if (!line) {
        return null
      }
    } else {
      n = lineNo(line)
      if (n == null) {
        return null
      }
    }
    return {
      line: n,
      handle: line,
      text: line.text,
      gutterMarkers: line.gutterMarkers,
      textClass: line.textClass,
      bgClass: line.bgClass,
      wrapClass: line.wrapClass,
      widgets: line.widgets
    }
  },

  addLineClass: docMethodOp(function (handle, where, cls) {
    return changeLine(this, handle, where == 'gutter' ? 'gutter' : 'class', function (line) {
      var prop = where == 'text' ? 'textClass'
        : where == 'background' ? 'bgClass'
          : where == 'gutter' ? 'gutterClass' : 'wrapClass'
      if (!line[prop]) {
        line[prop] = cls
      } else if (classTest(cls).test(line[prop])) {
        return false
      } else {
        line[prop] += ' ' + cls
      }
      return true
    })
  }),
  removeLineClass: docMethodOp(function (handle, where, cls) {
    return changeLine(this, handle, where == 'gutter' ? 'gutter' : 'class', function (line) {
      var prop = where == 'text' ? 'textClass'
        : where == 'background' ? 'bgClass'
          : where == 'gutter' ? 'gutterClass' : 'wrapClass'
      var cur = line[prop]
      if (!cur) {
        return false
      } else if (cls == null) {
        line[prop] = null
      } else {
        var found = cur.match(classTest(cls))
        if (!found) {
          return false
        }
        var end = found.index + found[0].length
        line[prop] = cur.slice(0, found.index) + (!found.index || end == cur.length ? '' : ' ') + cur.slice(end) || null
      }
      return true
    })
  }),

  addLineWidget: docMethodOp(function (handle, node, options) {
    return addLineWidget(this, handle, node, options)
  }),
  removeLineWidget: function (widget) {
    widget.clear()
  },

  markText: function (from, to, options) {
    return markText(this, clipPos(this, from), clipPos(this, to), options, options && options.type || 'range')
  },
  setBookmark: function (pos, options) {
    var realOpts = {
      replacedWith: options && (options.nodeType == null ? options.widget : options),
      insertLeft: options && options.insertLeft,
      clearWhenEmpty: false,
      shared: options && options.shared,
      handleMouseEvents: options && options.handleMouseEvents
    }
    pos = clipPos(this, pos)
    return markText(this, pos, pos, realOpts, 'bookmark')
  },
  findMarksAt: function (pos) {
    pos = clipPos(this, pos)
    var markers = []; var spans = getLine(this, pos.line).markedSpans
    if (spans) {
      for (var i = 0; i < spans.length; ++i) {
        var span = spans[i]
        if ((span.from == null || span.from <= pos.ch) &&
                    (span.to == null || span.to >= pos.ch)) {
          markers.push(span.marker.parent || span.marker)
        }
      }
    }
    return markers
  },
  findMarks: function (from, to, filter) {
    from = clipPos(this, from)
    to = clipPos(this, to)
    var found = []; var lineNo$$1 = from.line
    this.iter(from.line, to.line + 1, function (line) {
      var spans = line.markedSpans
      if (spans) {
        for (var i = 0; i < spans.length; i++) {
          var span = spans[i]
          if (!(span.to != null && lineNo$$1 == from.line && from.ch >= span.to ||
                        span.from == null && lineNo$$1 != from.line ||
                        span.from != null && lineNo$$1 == to.line && span.from >= to.ch) &&
                        (!filter || filter(span.marker))) {
            found.push(span.marker.parent || span.marker)
          }
        }
      }
      ++lineNo$$1
    })
    return found
  },
  getAllMarks: function () {
    var markers = []
    this.iter(function (line) {
      var sps = line.markedSpans
      if (sps) {
        for (var i = 0; i < sps.length; ++i) {
          if (sps[i].from != null) {
            markers.push(sps[i].marker)
          }
        }
      }
    })
    return markers
  },

  posFromIndex: function (off) {
    var ch; var lineNo$$1 = this.first; var sepSize = this.lineSeparator().length
    this.iter(function (line) {
      var sz = line.text.length + sepSize
      if (sz > off) {
        ch = off
        return true
      }
      off -= sz
      ++lineNo$$1
    })
    return clipPos(this, Pos(lineNo$$1, ch))
  },
  indexFromPos: function (coords) {
    coords = clipPos(this, coords)
    var index = coords.ch
    if (coords.line < this.first || coords.ch < 0) {
      return 0
    }
    var sepSize = this.lineSeparator().length
    this.iter(this.first, coords.line, function (line) { // iter aborts when callback returns a truthy value
      index += line.text.length + sepSize
    })
    return index
  },

  copy: function (copyHistory) {
    var doc = new Doc(getLines(this, this.first, this.first + this.size),
      this.modeOption, this.first, this.lineSep, this.direction)
    doc.scrollTop = this.scrollTop
    doc.scrollLeft = this.scrollLeft
    doc.sel = this.sel
    doc.extend = false
    if (copyHistory) {
      doc.history.undoDepth = this.history.undoDepth
      doc.setHistory(this.getHistory())
    }
    return doc
  },

  linkedDoc: function (options) {
    if (!options) {
      options = {}
    }
    var from = this.first; var to = this.first + this.size
    if (options.from != null && options.from > from) {
      from = options.from
    }
    if (options.to != null && options.to < to) {
      to = options.to
    }
    var copy = new Doc(getLines(this, from, to), options.mode || this.modeOption, from, this.lineSep, this.direction)
    if (options.sharedHist) {
      copy.history = this.history
    }
    (this.linked || (this.linked = [])).push({ doc: copy, sharedHist: options.sharedHist })
    copy.linked = [{ doc: this, isParent: true, sharedHist: options.sharedHist }]
    copySharedMarkers(copy, findSharedMarkers(this))
    return copy
  },
  unlinkDoc: function (other) {
    var this$1 = this

    if (other instanceof CodeMirror) {
      other = other.doc
    }
    if (this.linked) {
      for (var i = 0; i < this.linked.length; ++i) {
        var link = this$1.linked[i]
        if (link.doc != other) {
          continue
        }
        this$1.linked.splice(i, 1)
        other.unlinkDoc(this$1)
        detachSharedMarkers(findSharedMarkers(this$1))
        break
      }
    }
    // If the histories were shared, split them again
    if (other.history == this.history) {
      var splitIds = [other.id]
      linkedDocs(other, function (doc) {
        return splitIds.push(doc.id)
      }, true)
      other.history = new History(null)
      other.history.done = copyHistoryArray(this.history.done, splitIds)
      other.history.undone = copyHistoryArray(this.history.undone, splitIds)
    }
  },
  iterLinkedDocs: function (f) {
    linkedDocs(this, f)
  },

  getMode: function () {
    return this.mode
  },
  getEditor: function () {
    return this.cm
  },

  splitLines: function (str) {
    if (this.lineSep) {
      return str.split(this.lineSep)
    }
    return splitLinesAuto(str)
  },
  lineSeparator: function () {
    return this.lineSep || '\n'
  },

  setDirection: docMethodOp(function (dir) {
    if (dir != 'rtl') {
      dir = 'ltr'
    }
    if (dir == this.direction) {
      return
    }
    this.direction = dir
    this.iter(function (line) {
      return line.order = null
    })
    if (this.cm) {
      directionChanged(this.cm)
    }
  })
})

// Public alias.
Doc.prototype.eachLine = Doc.prototype.iter

// Kludge to work around strange IE behavior where it'll sometimes
// re-fire a series of drag-related events right after the drop (#1551)
var lastDrop = 0

function onDrop (e) {
  var cm = this
  clearDragCursor(cm)
  if (signalDOMEvent(cm, e) || eventInWidget(cm.display, e)) {
    return
  }
  e_preventDefault(e)
  if (ie) {
    lastDrop = +new Date()
  }
  var pos = posFromMouse(cm, e, true); var files = e.dataTransfer.files
  if (!pos || cm.isReadOnly()) {
    return
  }
  // Might be a file drop, in which case we simply extract the text
  // and insert it.
  if (files && files.length && window.FileReader && window.File) {
    var n = files.length; var text = Array(n); var read = 0
    var loadFile = function (file, i) {
      if (cm.options.allowDropFileTypes &&
                indexOf(cm.options.allowDropFileTypes, file.type) == -1) {
        return
      }

      var reader = new FileReader()
      reader.onload = operation(cm, function () {
        var content = reader.result
        if (/[\x00-\x08\x0e-\x1f]{2}/.test(content)) {
          content = ''
        }
        text[i] = content
        if (++read == n) {
          pos = clipPos(cm.doc, pos)
          var change = {
            from: pos,
            to: pos,
            text: cm.doc.splitLines(text.join(cm.doc.lineSeparator())),
            origin: 'paste'
          }
          makeChange(cm.doc, change)
          setSelectionReplaceHistory(cm.doc, simpleSelection(pos, changeEnd(change)))
        }
      })
      reader.readAsText(file)
    }
    for (var i = 0; i < n; ++i) {
      loadFile(files[i], i)
    }
  } else { // Normal drop
    // Don't do a replace if the drop happened inside of the selected text.
    if (cm.state.draggingText && cm.doc.sel.contains(pos) > -1) {
      cm.state.draggingText(e)
      // Ensure the src is re-focused
      setTimeout(function () {
        return cm.display.input.focus()
      }, 20)
      return
    }
    try {
      var text$1 = e.dataTransfer.getData('Text')
      if (text$1) {
        var selected
        if (cm.state.draggingText && !cm.state.draggingText.copy) {
          selected = cm.listSelections()
        }
        setSelectionNoUndo(cm.doc, simpleSelection(pos, pos))
        if (selected) {
          for (var i$1 = 0; i$1 < selected.length; ++i$1) {
            replaceRange(cm.doc, '', selected[i$1].anchor, selected[i$1].head, 'drag')
          }
        }
        cm.replaceSelection(text$1, 'around', 'paste')
        cm.display.input.focus()
      }
    } catch (e) {
    }
  }
}

function onDragStart (cm, e) {
  if (ie && (!cm.state.draggingText || +new Date() - lastDrop < 100)) {
    e_stop(e)
    return
  }
  if (signalDOMEvent(cm, e) || eventInWidget(cm.display, e)) {
    return
  }

  e.dataTransfer.setData('Text', cm.getSelection())
  e.dataTransfer.effectAllowed = 'copyMove'

  // Use dummy image instead of default browsers image.
  // Recent Safari (~6.0.2) have a tendency to segfault when this happens, so we don't do it there.
  if (e.dataTransfer.setDragImage && !safari) {
    var img = elt('img', null, null, 'position: fixed; left: 0; top: 0;')
    img.src = ''
    if (presto) {
      img.width = img.height = 1
      cm.display.wrapper.appendChild(img)
      // Force a relayout, or Opera won't use our image for some obscure reason
      img._top = img.offsetTop
    }
    e.dataTransfer.setDragImage(img, 0, 0)
    if (presto) {
      img.parentNode.removeChild(img)
    }
  }
}

function onDragOver (cm, e) {
  var pos = posFromMouse(cm, e)
  if (!pos) {
    return
  }
  var frag = document.createDocumentFragment()
  drawSelectionCursor(cm, pos, frag)
  if (!cm.display.dragCursor) {
    cm.display.dragCursor = elt('div', null, 'CodeMirror-cursors CodeMirror-dragcursors')
    cm.display.lineSpace.insertBefore(cm.display.dragCursor, cm.display.cursorDiv)
  }
  removeChildrenAndAdd(cm.display.dragCursor, frag)
}

function clearDragCursor (cm) {
  if (cm.display.dragCursor) {
    cm.display.lineSpace.removeChild(cm.display.dragCursor)
    cm.display.dragCursor = null
  }
}

// These must be handled carefully, because naively registering a
// handler for each src will cause the editors to never be
// garbage collected.

function forEachCodeMirror (f) {
  if (!document.getElementsByClassName) {
    return
  }
  var byClass = document.getElementsByClassName('CodeMirror'); var editors = []
  for (var i = 0; i < byClass.length; i++) {
    var cm = byClass[i].CodeMirror
    if (cm) {
      editors.push(cm)
    }
  }
  if (editors.length) {
    editors[0].operation(function () {
      for (var i = 0; i < editors.length; i++) {
        f(editors[i])
      }
    })
  }
}

var globalsRegistered = false

function ensureGlobalHandlers () {
  if (globalsRegistered) {
    return
  }
  registerGlobalHandlers()
  globalsRegistered = true
}

function registerGlobalHandlers () {
  // When the window resizes, we need to refresh active editors.
  var resizeTimer
  on(window, 'resize', function () {
    if (resizeTimer == null) {
      resizeTimer = setTimeout(function () {
        resizeTimer = null
        forEachCodeMirror(onResize)
      }, 100)
    }
  })
  // When the window loses focus, we want to show the src as blurred
  on(window, 'blur', function () {
    return forEachCodeMirror(onBlur)
  })
}

// Called when the window resizes
function onResize (cm) {
  var d = cm.display
  // Might be a text scaling operation, clear size caches.
  d.cachedCharWidth = d.cachedTextHeight = d.cachedPaddingH = null
  d.scrollbarsClipped = false
  cm.setSize()
}

var keyNames = {
  3: 'Pause',
  8: 'Backspace',
  9: 'Tab',
  13: 'Enter',
  16: 'Shift',
  17: 'Ctrl',
  18: 'Alt',
  19: 'Pause',
  20: 'CapsLock',
  27: 'Esc',
  32: 'Space',
  33: 'PageUp',
  34: 'PageDown',
  35: 'End',
  36: 'Home',
  37: 'Left',
  38: 'Up',
  39: 'Right',
  40: 'Down',
  44: 'PrintScrn',
  45: 'Insert',
  46: 'Delete',
  59: ';',
  61: '=',
  91: 'Mod',
  92: 'Mod',
  93: 'Mod',
  106: '*',
  107: '=',
  109: '-',
  110: '.',
  111: '/',
  145: 'ScrollLock',
  173: '-',
  186: ';',
  187: '=',
  188: ',',
  189: '-',
  190: '.',
  191: '/',
  192: '`',
  219: '[',
  220: '\\',
  221: ']',
  222: "'",
  63232: 'Up',
  63233: 'Down',
  63234: 'Left',
  63235: 'Right',
  63272: 'Delete',
  63273: 'Home',
  63275: 'End',
  63276: 'PageUp',
  63277: 'PageDown',
  63302: 'Insert'
}

// Number keys
for (var i = 0; i < 10; i++) {
  keyNames[i + 48] = keyNames[i + 96] = String(i)
}
// Alphabetic keys
for (var i$1 = 65; i$1 <= 90; i$1++) {
  keyNames[i$1] = String.fromCharCode(i$1)
}
// Function keys
for (var i$2 = 1; i$2 <= 12; i$2++) {
  keyNames[i$2 + 111] = keyNames[i$2 + 63235] = 'F' + i$2
}

var keyMap = {}

keyMap.basic = {
  Left: 'goCharLeft',
  Right: 'goCharRight',
  Up: 'goLineUp',
  Down: 'goLineDown',
  End: 'goLineEnd',
  Home: 'goLineStartSmart',
  PageUp: 'goPageUp',
  PageDown: 'goPageDown',
  Delete: 'delCharAfter',
  Backspace: 'delCharBefore',
  'Shift-Backspace': 'delCharBefore',
  Tab: 'defaultTab',
  'Shift-Tab': 'indentAuto',
  Enter: 'newlineAndIndent',
  Insert: 'toggleOverwrite',
  Esc: 'singleSelection'
}
// Note that the save and find-related commands aren't defined by
// default. User code or addons can define them. Unknown commands
// are simply ignored.
keyMap.pcDefault = {
  'Ctrl-A': 'selectAll',
  'Ctrl-D': 'deleteLine',
  'Ctrl-Z': 'undo',
  'Shift-Ctrl-Z': 'redo',
  'Ctrl-Y': 'redo',
  'Ctrl-Home': 'goDocStart',
  'Ctrl-End': 'goDocEnd',
  'Ctrl-Up': 'goLineUp',
  'Ctrl-Down': 'goLineDown',
  'Ctrl-Left': 'goGroupLeft',
  'Ctrl-Right': 'goGroupRight',
  'Alt-Left': 'goLineStart',
  'Alt-Right': 'goLineEnd',
  'Ctrl-Backspace': 'delGroupBefore',
  'Ctrl-Delete': 'delGroupAfter',
  'Ctrl-S': 'save',
  'Ctrl-F': 'find',
  'Ctrl-G': 'findNext',
  'Shift-Ctrl-G': 'findPrev',
  'Shift-Ctrl-F': 'replace',
  'Shift-Ctrl-R': 'replaceAll',
  'Ctrl-[': 'indentLess',
  'Ctrl-]': 'indentMore',
  'Ctrl-U': 'undoSelection',
  'Shift-Ctrl-U': 'redoSelection',
  'Alt-U': 'redoSelection',
  fallthrough: 'basic'
}
// Very basic readline/emacs-style bindings, which are standard on Mac.
keyMap.emacsy = {
  'Ctrl-F': 'goCharRight',
  'Ctrl-B': 'goCharLeft',
  'Ctrl-P': 'goLineUp',
  'Ctrl-N': 'goLineDown',
  'Alt-F': 'goWordRight',
  'Alt-B': 'goWordLeft',
  'Ctrl-A': 'goLineStart',
  'Ctrl-E': 'goLineEnd',
  'Ctrl-V': 'goPageDown',
  'Shift-Ctrl-V': 'goPageUp',
  'Ctrl-D': 'delCharAfter',
  'Ctrl-H': 'delCharBefore',
  'Alt-D': 'delWordAfter',
  'Alt-Backspace': 'delWordBefore',
  'Ctrl-K': 'killLine',
  'Ctrl-T': 'transposeChars',
  'Ctrl-O': 'openLine'
}
keyMap.macDefault = {
  'Cmd-A': 'selectAll',
  'Cmd-D': 'deleteLine',
  'Cmd-Z': 'undo',
  'Shift-Cmd-Z': 'redo',
  'Cmd-Y': 'redo',
  'Cmd-Home': 'goDocStart',
  'Cmd-Up': 'goDocStart',
  'Cmd-End': 'goDocEnd',
  'Cmd-Down': 'goDocEnd',
  'Alt-Left': 'goGroupLeft',
  'Alt-Right': 'goGroupRight',
  'Cmd-Left': 'goLineLeft',
  'Cmd-Right': 'goLineRight',
  'Alt-Backspace': 'delGroupBefore',
  'Ctrl-Alt-Backspace': 'delGroupAfter',
  'Alt-Delete': 'delGroupAfter',
  'Cmd-S': 'save',
  'Cmd-F': 'find',
  'Cmd-G': 'findNext',
  'Shift-Cmd-G': 'findPrev',
  'Cmd-Alt-F': 'replace',
  'Shift-Cmd-Alt-F': 'replaceAll',
  'Cmd-[': 'indentLess',
  'Cmd-]': 'indentMore',
  'Cmd-Backspace': 'delWrappedLineLeft',
  'Cmd-Delete': 'delWrappedLineRight',
  'Cmd-U': 'undoSelection',
  'Shift-Cmd-U': 'redoSelection',
  'Ctrl-Up': 'goDocStart',
  'Ctrl-Down': 'goDocEnd',
  fallthrough: ['basic', 'emacsy']
}
keyMap.default = mac ? keyMap.macDefault : keyMap.pcDefault

// KEYMAP DISPATCH

function normalizeKeyName (name) {
  var parts = name.split(/-(?!$)/)
  name = parts[parts.length - 1]
  var alt, ctrl, shift, cmd
  for (var i = 0; i < parts.length - 1; i++) {
    var mod = parts[i]
    if (/^(cmd|meta|m)$/i.test(mod)) {
      cmd = true
    } else if (/^a(lt)?$/i.test(mod)) {
      alt = true
    } else if (/^(c|ctrl|control)$/i.test(mod)) {
      ctrl = true
    } else if (/^s(hift)?$/i.test(mod)) {
      shift = true
    } else {
      throw new Error('Unrecognized modifier name: ' + mod)
    }
  }
  if (alt) {
    name = 'Alt-' + name
  }
  if (ctrl) {
    name = 'Ctrl-' + name
  }
  if (cmd) {
    name = 'Cmd-' + name
  }
  if (shift) {
    name = 'Shift-' + name
  }
  return name
}

// This is a kludge to keep keymaps mostly working as raw objects
// (backwards compatibility) while at the same time support features
// like normalization and multi-stroke key bindings. It compiles a
// new normalized keymap, and then updates the old object to reflect
// this.
function normalizeKeyMap (keymap) {
  var copy = {}
  for (var keyname in keymap) {
    if (keymap.hasOwnProperty(keyname)) {
      var value = keymap[keyname]
      if (/^(name|fallthrough|(de|at)tach)$/.test(keyname)) {
        continue
      }
      if (value == '...') {
        delete keymap[keyname]
        continue
      }

      var keys = map(keyname.split(' '), normalizeKeyName)
      for (var i = 0; i < keys.length; i++) {
        var val = (void 0); var name = (void 0)
        if (i == keys.length - 1) {
          name = keys.join(' ')
          val = value
        } else {
          name = keys.slice(0, i + 1).join(' ')
          val = '...'
        }
        var prev = copy[name]
        if (!prev) {
          copy[name] = val
        } else if (prev != val) {
          throw new Error('Inconsistent bindings for ' + name)
        }
      }
      delete keymap[keyname]
    }
  }
  for (var prop in copy) {
    keymap[prop] = copy[prop]
  }
  return keymap
}

function lookupKey (key, map$$1, handle, context) {
  map$$1 = getKeyMap(map$$1)
  var found = map$$1.call ? map$$1.call(key, context) : map$$1[key]
  if (found === false) {
    return 'nothing'
  }
  if (found === '...') {
    return 'multi'
  }
  if (found != null && handle(found)) {
    return 'handled'
  }

  if (map$$1.fallthrough) {
    if (Object.prototype.toString.call(map$$1.fallthrough) != '[object Array]') {
      return lookupKey(key, map$$1.fallthrough, handle, context)
    }
    for (var i = 0; i < map$$1.fallthrough.length; i++) {
      var result = lookupKey(key, map$$1.fallthrough[i], handle, context)
      if (result) {
        return result
      }
    }
  }
}

// Modifier key presses don't count as 'real' key presses for the
// purpose of keymap fallthrough.
function isModifierKey (value) {
  var name = typeof value === 'string' ? value : keyNames[value.keyCode]
  return name == 'Ctrl' || name == 'Alt' || name == 'Shift' || name == 'Mod'
}

function addModifierNames (name, event, noShift) {
  var base = name
  if (event.altKey && base != 'Alt') {
    name = 'Alt-' + name
  }
  if ((flipCtrlCmd ? event.metaKey : event.ctrlKey) && base != 'Ctrl') {
    name = 'Ctrl-' + name
  }
  if ((flipCtrlCmd ? event.ctrlKey : event.metaKey) && base != 'Cmd') {
    name = 'Cmd-' + name
  }
  if (!noShift && event.shiftKey && base != 'Shift') {
    name = 'Shift-' + name
  }
  return name
}

// Look up the name of a key as indicated by an event object.
function keyName (event, noShift) {
  if (presto && event.keyCode == 34 && event.char) {
    return false
  }
  var name = keyNames[event.keyCode]
  if (name == null || event.altGraphKey) {
    return false
  }
  // Ctrl-ScrollLock has keyCode 3, same as Ctrl-Pause,
  // so we'll use event.code when available (Chrome 48+, FF 38+, Safari 10.1+)
  if (event.keyCode == 3 && event.code) {
    name = event.code
  }
  return addModifierNames(name, event, noShift)
}

function getKeyMap (val) {
  return typeof val === 'string' ? keyMap[val] : val
}

// Helper for deleting text near the selection(s), used to implement
// backspace, delete, and similar functionality.
function deleteNearSelection (cm, compute) {
  var ranges = cm.doc.sel.ranges; var kill = []
  // Build up a set of ranges to kill first, merging overlapping
  // ranges.
  for (var i = 0; i < ranges.length; i++) {
    var toKill = compute(ranges[i])
    while (kill.length && cmp(toKill.from, lst(kill).to) <= 0) {
      var replaced = kill.pop()
      if (cmp(replaced.from, toKill.from) < 0) {
        toKill.from = replaced.from
        break
      }
    }
    kill.push(toKill)
  }
  // Next, remove those actual ranges.
  runInOp(cm, function () {
    for (var i = kill.length - 1; i >= 0; i--) {
      replaceRange(cm.doc, '', kill[i].from, kill[i].to, '+delete')
    }
    ensureCursorVisible(cm)
  })
}

function moveCharLogically (line, ch, dir) {
  var target = skipExtendingChars(line.text, ch + dir, dir)
  return target < 0 || target > line.text.length ? null : target
}

function moveLogically (line, start, dir) {
  var ch = moveCharLogically(line, start.ch, dir)
  return ch == null ? null : new Pos(start.line, ch, dir < 0 ? 'after' : 'before')
}

function endOfLine (visually, cm, lineObj, lineNo, dir) {
  if (visually) {
    var order = getOrder(lineObj, cm.doc.direction)
    if (order) {
      var part = dir < 0 ? lst(order) : order[0]
      var moveInStorageOrder = (dir < 0) == (part.level == 1)
      var sticky = moveInStorageOrder ? 'after' : 'before'
      var ch
      if (part.level > 0 || cm.doc.direction == 'rtl') {
        var prep = prepareMeasureForLine(cm, lineObj)
        ch = dir < 0 ? lineObj.text.length - 1 : 0
        var targetTop = measureCharPrepared(cm, prep, ch).top
        ch = findFirst(function (ch) {
          return measureCharPrepared(cm, prep, ch).top == targetTop
        }, (dir < 0) == (part.level == 1) ? part.from : part.to - 1, ch)
        if (sticky == 'before') {
          ch = moveCharLogically(lineObj, ch, 1)
        }
      } else {
        ch = dir < 0 ? part.to : part.from
      }
      return new Pos(lineNo, ch, sticky)
    }
  }
  return new Pos(lineNo, dir < 0 ? lineObj.text.length : 0, dir < 0 ? 'before' : 'after')
}

function moveVisually (cm, line, start, dir) {
  var bidi = getOrder(line, cm.doc.direction)
  if (!bidi) {
    return moveLogically(line, start, dir)
  }
  if (start.ch >= line.text.length) {
    start.ch = line.text.length
    start.sticky = 'before'
  } else if (start.ch <= 0) {
    start.ch = 0
    start.sticky = 'after'
  }
  var partPos = getBidiPartAt(bidi, start.ch, start.sticky); var part = bidi[partPos]
  if (cm.doc.direction == 'ltr' && part.level % 2 == 0 && (dir > 0 ? part.to > start.ch : part.from < start.ch)) {
    // Case 1: We move within an ltr part in an ltr src. Even with wrapped lines,
    // nothing interesting happens.
    return moveLogically(line, start, dir)
  }

  var mv = function (pos, dir) {
    return moveCharLogically(line, pos instanceof Pos ? pos.ch : pos, dir)
  }
  var prep
  var getWrappedLineExtent = function (ch) {
    if (!cm.options.lineWrapping) {
      return { begin: 0, end: line.text.length }
    }
    prep = prep || prepareMeasureForLine(cm, line)
    return wrappedLineExtentChar(cm, line, prep, ch)
  }
  var wrappedLineExtent = getWrappedLineExtent(start.sticky == 'before' ? mv(start, -1) : start.ch)

  if (cm.doc.direction == 'rtl' || part.level == 1) {
    var moveInStorageOrder = (part.level == 1) == (dir < 0)
    var ch = mv(start, moveInStorageOrder ? 1 : -1)
    if (ch != null && (!moveInStorageOrder ? ch >= part.from && ch >= wrappedLineExtent.begin : ch <= part.to && ch <= wrappedLineExtent.end)) {
      // Case 2: We move within an rtl part or in an rtl src on the same visual line
      var sticky = moveInStorageOrder ? 'before' : 'after'
      return new Pos(start.line, ch, sticky)
    }
  }

  // Case 3: Could not move within this bidi part in this visual line, so leave
  // the current bidi part

  var searchInVisualLine = function (partPos, dir, wrappedLineExtent) {
    var getRes = function (ch, moveInStorageOrder) {
      return moveInStorageOrder
        ? new Pos(start.line, mv(ch, 1), 'before')
        : new Pos(start.line, ch, 'after')
    }

    for (; partPos >= 0 && partPos < bidi.length; partPos += dir) {
      var part = bidi[partPos]
      var moveInStorageOrder = (dir > 0) == (part.level != 1)
      var ch = moveInStorageOrder ? wrappedLineExtent.begin : mv(wrappedLineExtent.end, -1)
      if (part.from <= ch && ch < part.to) {
        return getRes(ch, moveInStorageOrder)
      }
      ch = moveInStorageOrder ? part.from : mv(part.to, -1)
      if (wrappedLineExtent.begin <= ch && ch < wrappedLineExtent.end) {
        return getRes(ch, moveInStorageOrder)
      }
    }
  }

  // Case 3a: Look for other bidi parts on the same visual line
  var res = searchInVisualLine(partPos + dir, dir, wrappedLineExtent)
  if (res) {
    return res
  }

  // Case 3b: Look for other bidi parts on the next visual line
  var nextCh = dir > 0 ? wrappedLineExtent.end : mv(wrappedLineExtent.begin, -1)
  if (nextCh != null && !(dir > 0 && nextCh == line.text.length)) {
    res = searchInVisualLine(dir > 0 ? 0 : bidi.length - 1, dir, getWrappedLineExtent(nextCh))
    if (res) {
      return res
    }
  }

  // Case 4: Nowhere to move
  return null
}

// Commands are parameter-less actions that can be performed on an
// src, mostly used for keybindings.
var commands = {
  selectAll: selectAll,
  singleSelection: function (cm) {
    return cm.setSelection(cm.getCursor('anchor'), cm.getCursor('head'), sel_dontScroll)
  },
  killLine: function (cm) {
    return deleteNearSelection(cm, function (range) {
      if (range.empty()) {
        var len = getLine(cm.doc, range.head.line).text.length
        if (range.head.ch == len && range.head.line < cm.lastLine()) {
          return { from: range.head, to: Pos(range.head.line + 1, 0) }
        } else {
          return { from: range.head, to: Pos(range.head.line, len) }
        }
      } else {
        return { from: range.from(), to: range.to() }
      }
    })
  },
  deleteLine: function (cm) {
    return deleteNearSelection(cm, function (range) {
      return ({
        from: Pos(range.from().line, 0),
        to: clipPos(cm.doc, Pos(range.to().line + 1, 0))
      })
    })
  },
  delLineLeft: function (cm) {
    return deleteNearSelection(cm, function (range) {
      return ({
        from: Pos(range.from().line, 0), to: range.from()
      })
    })
  },
  delWrappedLineLeft: function (cm) {
    return deleteNearSelection(cm, function (range) {
      var top = cm.charCoords(range.head, 'div').top + 5
      var leftPos = cm.coordsChar({ left: 0, top: top }, 'div')
      return { from: leftPos, to: range.from() }
    })
  },
  delWrappedLineRight: function (cm) {
    return deleteNearSelection(cm, function (range) {
      var top = cm.charCoords(range.head, 'div').top + 5
      var rightPos = cm.coordsChar({ left: cm.display.lineDiv.offsetWidth + 100, top: top }, 'div')
      return { from: range.from(), to: rightPos }
    })
  },
  undo: function (cm) {
    return cm.undo()
  },
  redo: function (cm) {
    return cm.redo()
  },
  undoSelection: function (cm) {
    return cm.undoSelection()
  },
  redoSelection: function (cm) {
    return cm.redoSelection()
  },
  goDocStart: function (cm) {
    return cm.extendSelection(Pos(cm.firstLine(), 0))
  },
  goDocEnd: function (cm) {
    return cm.extendSelection(Pos(cm.lastLine()))
  },
  goLineStart: function (cm) {
    return cm.extendSelectionsBy(function (range) {
      return lineStart(cm, range.head.line)
    },
    { origin: '+move', bias: 1 }
    )
  },
  goLineStartSmart: function (cm) {
    return cm.extendSelectionsBy(function (range) {
      return lineStartSmart(cm, range.head)
    },
    { origin: '+move', bias: 1 }
    )
  },
  goLineEnd: function (cm) {
    return cm.extendSelectionsBy(function (range) {
      return lineEnd(cm, range.head.line)
    },
    { origin: '+move', bias: -1 }
    )
  },
  goLineRight: function (cm) {
    return cm.extendSelectionsBy(function (range) {
      var top = cm.cursorCoords(range.head, 'div').top + 5
      return cm.coordsChar({ left: cm.display.lineDiv.offsetWidth + 100, top: top }, 'div')
    }, sel_move)
  },
  goLineLeft: function (cm) {
    return cm.extendSelectionsBy(function (range) {
      var top = cm.cursorCoords(range.head, 'div').top + 5
      return cm.coordsChar({ left: 0, top: top }, 'div')
    }, sel_move)
  },
  goLineLeftSmart: function (cm) {
    return cm.extendSelectionsBy(function (range) {
      var top = cm.cursorCoords(range.head, 'div').top + 5
      var pos = cm.coordsChar({ left: 0, top: top }, 'div')
      if (pos.ch < cm.getLine(pos.line).search(/\S/)) {
        return lineStartSmart(cm, range.head)
      }
      return pos
    }, sel_move)
  },
  goLineUp: function (cm) {
    return cm.moveV(-1, 'line')
  },
  goLineDown: function (cm) {
    return cm.moveV(1, 'line')
  },
  goPageUp: function (cm) {
    return cm.moveV(-1, 'page')
  },
  goPageDown: function (cm) {
    return cm.moveV(1, 'page')
  },
  goCharLeft: function (cm) {
    return cm.moveH(-1, 'char')
  },
  goCharRight: function (cm) {
    return cm.moveH(1, 'char')
  },
  goColumnLeft: function (cm) {
    return cm.moveH(-1, 'column')
  },
  goColumnRight: function (cm) {
    return cm.moveH(1, 'column')
  },
  goWordLeft: function (cm) {
    return cm.moveH(-1, 'word')
  },
  goGroupRight: function (cm) {
    return cm.moveH(1, 'group')
  },
  goGroupLeft: function (cm) {
    return cm.moveH(-1, 'group')
  },
  goWordRight: function (cm) {
    return cm.moveH(1, 'word')
  },
  delCharBefore: function (cm) {
    return cm.deleteH(-1, 'char')
  },
  delCharAfter: function (cm) {
    return cm.deleteH(1, 'char')
  },
  delWordBefore: function (cm) {
    return cm.deleteH(-1, 'word')
  },
  delWordAfter: function (cm) {
    return cm.deleteH(1, 'word')
  },
  delGroupBefore: function (cm) {
    return cm.deleteH(-1, 'group')
  },
  delGroupAfter: function (cm) {
    return cm.deleteH(1, 'group')
  },
  indentAuto: function (cm) {
    return cm.indentSelection('smart')
  },
  indentMore: function (cm) {
    return cm.indentSelection('add')
  },
  indentLess: function (cm) {
    return cm.indentSelection('subtract')
  },
  insertTab: function (cm) {
    return cm.replaceSelection('\t')
  },
  insertSoftTab: function (cm) {
    var spaces = []; var ranges = cm.listSelections(); var tabSize = cm.options.tabSize
    for (var i = 0; i < ranges.length; i++) {
      var pos = ranges[i].from()
      var col = countColumn(cm.getLine(pos.line), pos.ch, tabSize)
      spaces.push(spaceStr(tabSize - col % tabSize))
    }
    cm.replaceSelections(spaces)
  },
  defaultTab: function (cm) {
    if (cm.somethingSelected()) {
      cm.indentSelection('add')
    } else {
      cm.execCommand('insertTab')
    }
  },
  // Swap the two chars left and right of each selection's head.
  // Move cursor behind the two swapped characters afterwards.
  //
  // Doesn't consider line feeds a character.
  // Doesn't scan more than one line above to find a character.
  // Doesn't do anything on an empty line.
  // Doesn't do anything with non-empty selections.
  transposeChars: function (cm) {
    return runInOp(cm, function () {
      var ranges = cm.listSelections(); var newSel = []
      for (var i = 0; i < ranges.length; i++) {
        if (!ranges[i].empty()) {
          continue
        }
        var cur = ranges[i].head; var line = getLine(cm.doc, cur.line).text
        if (line) {
          if (cur.ch == line.length) {
            cur = new Pos(cur.line, cur.ch - 1)
          }
          if (cur.ch > 0) {
            cur = new Pos(cur.line, cur.ch + 1)
            cm.replaceRange(line.charAt(cur.ch - 1) + line.charAt(cur.ch - 2),
              Pos(cur.line, cur.ch - 2), cur, '+transpose')
          } else if (cur.line > cm.doc.first) {
            var prev = getLine(cm.doc, cur.line - 1).text
            if (prev) {
              cur = new Pos(cur.line, 1)
              cm.replaceRange(line.charAt(0) + cm.doc.lineSeparator() +
                                prev.charAt(prev.length - 1),
              Pos(cur.line - 1, prev.length - 1), cur, '+transpose')
            }
          }
        }
        newSel.push(new Range(cur, cur))
      }
      cm.setSelections(newSel)
    })
  },
  newlineAndIndent: function (cm) {
    return runInOp(cm, function () {
      var sels = cm.listSelections()
      for (var i = sels.length - 1; i >= 0; i--) {
        cm.replaceRange(cm.doc.lineSeparator(), sels[i].anchor, sels[i].head, '+input')
      }
      sels = cm.listSelections()
      for (var i$1 = 0; i$1 < sels.length; i$1++) {
        cm.indentLine(sels[i$1].from().line, null, true)
      }
      ensureCursorVisible(cm)
    })
  },
  openLine: function (cm) {
    return cm.replaceSelection('\n', 'start')
  },
  toggleOverwrite: function (cm) {
    return cm.toggleOverwrite()
  }
}

function lineStart (cm, lineN) {
  var line = getLine(cm.doc, lineN)
  var visual = visualLine(line)
  if (visual != line) {
    lineN = lineNo(visual)
  }
  return endOfLine(true, cm, visual, lineN, 1)
}

function lineEnd (cm, lineN) {
  var line = getLine(cm.doc, lineN)
  var visual = visualLineEnd(line)
  if (visual != line) {
    lineN = lineNo(visual)
  }
  return endOfLine(true, cm, line, lineN, -1)
}

function lineStartSmart (cm, pos) {
  var start = lineStart(cm, pos.line)
  var line = getLine(cm.doc, start.line)
  var order = getOrder(line, cm.doc.direction)
  if (!order || order[0].level == 0) {
    var firstNonWS = Math.max(0, line.text.search(/\S/))
    var inWS = pos.line == start.line && pos.ch <= firstNonWS && pos.ch
    return Pos(start.line, inWS ? 0 : firstNonWS, start.sticky)
  }
  return start
}

// Run a handler that was bound to a key.
function doHandleBinding (cm, bound, dropShift) {
  if (typeof bound === 'string') {
    bound = commands[bound]
    if (!bound) {
      return false
    }
  }
  // Ensure previous input has been read, so that the handler sees a
  // consistent view of the document
  cm.display.input.ensurePolled()
  var prevShift = cm.display.shift; var done = false
  try {
    if (cm.isReadOnly()) {
      cm.state.suppressEdits = true
    }
    if (dropShift) {
      cm.display.shift = false
    }
    done = bound(cm) != Pass
  } finally {
    cm.display.shift = prevShift
    cm.state.suppressEdits = false
  }
  return done
}

function lookupKeyForEditor (cm, name, handle) {
  for (var i = 0; i < cm.state.keyMaps.length; i++) {
    var result = lookupKey(name, cm.state.keyMaps[i], handle, cm)
    if (result) {
      return result
    }
  }
  return (cm.options.extraKeys && lookupKey(name, cm.options.extraKeys, handle, cm)) ||
        lookupKey(name, cm.options.keyMap, handle, cm)
}

// Note that, despite the name, this function is also used to check
// for bound mouse clicks.

var stopSeq = new Delayed()

function dispatchKey (cm, name, e, handle) {
  var seq = cm.state.keySeq
  if (seq) {
    if (isModifierKey(name)) {
      return 'handled'
    }
    if (/\'$/.test(name)) {
      cm.state.keySeq = null
    } else {
      stopSeq.set(50, function () {
        if (cm.state.keySeq == seq) {
          cm.state.keySeq = null
          cm.display.input.reset()
        }
      })
    }
    if (dispatchKeyInner(cm, seq + ' ' + name, e, handle)) {
      return true
    }
  }
  return dispatchKeyInner(cm, name, e, handle)
}

function dispatchKeyInner (cm, name, e, handle) {
  var result = lookupKeyForEditor(cm, name, handle)

  if (result == 'multi') {
    cm.state.keySeq = name
  }
  if (result == 'handled') {
    signalLater(cm, 'keyHandled', cm, name, e)
  }

  if (result == 'handled' || result == 'multi') {
    e_preventDefault(e)
    restartBlink(cm)
  }

  return !!result
}

// Handle a key from the keydown event.
function handleKeyBinding (cm, e) {
  var name = keyName(e, true)
  if (!name) {
    return false
  }

  if (e.shiftKey && !cm.state.keySeq) {
    // First try to resolve full name (including 'Shift-'). Failing
    // that, see if there is a cursor-motion command (starting with
    // 'go') bound to the keyname without 'Shift-'.
    return dispatchKey(cm, 'Shift-' + name, e, function (b) {
      return doHandleBinding(cm, b, true)
    }) ||
            dispatchKey(cm, name, e, function (b) {
              if (typeof b === 'string' ? /^go[A-Z]/.test(b) : b.motion) {
                return doHandleBinding(cm, b)
              }
            })
  } else {
    return dispatchKey(cm, name, e, function (b) {
      return doHandleBinding(cm, b)
    })
  }
}

// Handle a key from the keypress event
function handleCharBinding (cm, e, ch) {
  return dispatchKey(cm, "'" + ch + "'", e, function (b) {
    return doHandleBinding(cm, b, true)
  })
}

var lastStoppedKey = null

function onKeyDown (e) {
  var cm = this
  cm.curOp.focus = activeElt()
  if (signalDOMEvent(cm, e)) {
    return
  }
  // IE does strange things with escape.
  if (ie && ie_version < 11 && e.keyCode == 27) {
    e.returnValue = false
  }
  var code = e.keyCode
  cm.display.shift = code == 16 || e.shiftKey
  var handled = handleKeyBinding(cm, e)
  if (presto) {
    lastStoppedKey = handled ? code : null
    // Opera has no cut event... we try to at least catch the key combo
    if (!handled && code == 88 && !hasCopyEvent && (mac ? e.metaKey : e.ctrlKey)) {
      cm.replaceSelection('', null, 'cut')
    }
  }

  // Turn mouse into crosshair when Alt is held on Mac.
  if (code == 18 && !/\bCodeMirror-crosshair\b/.test(cm.display.lineDiv.className)) {
    showCrossHair(cm)
  }
}

function showCrossHair (cm) {
  var lineDiv = cm.display.lineDiv
  addClass(lineDiv, 'CodeMirror-crosshair')

  function up (e) {
    if (e.keyCode == 18 || !e.altKey) {
      rmClass(lineDiv, 'CodeMirror-crosshair')
      off(document, 'keyup', up)
      off(document, 'mouseover', up)
    }
  }

  on(document, 'keyup', up)
  on(document, 'mouseover', up)
}

function onKeyUp (e) {
  if (e.keyCode == 16) {
    this.doc.sel.shift = false
  }
  signalDOMEvent(this, e)
}

function onKeyPress (e) {
  var cm = this
  if (eventInWidget(cm.display, e) || signalDOMEvent(cm, e) || e.ctrlKey && !e.altKey || mac && e.metaKey) {
    return
  }
  var keyCode = e.keyCode; var charCode = e.charCode
  if (presto && keyCode == lastStoppedKey) {
    lastStoppedKey = null
    e_preventDefault(e)
    return
  }
  if ((presto && (!e.which || e.which < 10)) && handleKeyBinding(cm, e)) {
    return
  }
  var ch = String.fromCharCode(charCode == null ? keyCode : charCode)
  // Some browsers fire keypress events for backspace
  if (ch == '\x08') {
    return
  }
  if (handleCharBinding(cm, e, ch)) {
    return
  }
  cm.display.input.onKeyPress(e)
}

var DOUBLECLICK_DELAY = 400

var PastClick = function (time, pos, button) {
  this.time = time
  this.pos = pos
  this.button = button
}

PastClick.prototype.compare = function (time, pos, button) {
  return this.time + DOUBLECLICK_DELAY > time &&
        cmp(pos, this.pos) == 0 && button == this.button
}

var lastClick, lastDoubleClick

function clickRepeat (pos, button) {
  var now = +new Date()
  if (lastDoubleClick && lastDoubleClick.compare(now, pos, button)) {
    lastClick = lastDoubleClick = null
    return 'triple'
  } else if (lastClick && lastClick.compare(now, pos, button)) {
    lastDoubleClick = new PastClick(now, pos, button)
    lastClick = null
    return 'double'
  } else {
    lastClick = new PastClick(now, pos, button)
    lastDoubleClick = null
    return 'single'
  }
}

// A mouse down can be a single click, double click, triple click,
// start of selection drag, start of text drag, new cursor
// (ctrl-click), rectangle drag (alt-drag), or xwin
// middle-click-paste. Or it might be a click on something we should
// not interfere with, such as a scrollbar or widget.
function onMouseDown (e) {
  var cm = this; var display = cm.display
  if (signalDOMEvent(cm, e) || display.activeTouch && display.input.supportsTouch()) {
    return
  }
  display.input.ensurePolled()
  display.shift = e.shiftKey

  if (eventInWidget(display, e)) {
    if (!webkit) {
      // Briefly turn off draggability, to allow widgets to do
      // normal dragging things.
      display.scroller.draggable = false
      setTimeout(function () {
        return display.scroller.draggable = true
      }, 100)
    }
    return
  }
  if (clickInGutter(cm, e)) {
    return
  }
  var pos = posFromMouse(cm, e); var button = e_button(e); var repeat = pos ? clickRepeat(pos, button) : 'single'
  window.focus()

  // #3261: make sure, that we're not starting a second selection
  if (button == 1 && cm.state.selectingText) {
    cm.state.selectingText(e)
  }

  if (pos && handleMappedButton(cm, button, pos, repeat, e)) {
    return
  }

  if (button == 1) {
    if (pos) {
      leftButtonDown(cm, pos, repeat, e)
    } else if (e_target(e) == display.scroller) {
      e_preventDefault(e)
    }
  } else if (button == 2) {
    if (pos) {
      extendSelection(cm.doc, pos)
    }
    setTimeout(function () {
      return display.input.focus()
    }, 20)
  } else if (button == 3) {
    if (captureRightClick) {
      cm.display.input.onContextMenu(e)
    } else {
      delayBlurEvent(cm)
    }
  }
}

function handleMappedButton (cm, button, pos, repeat, event) {
  var name = 'Click'
  if (repeat == 'double') {
    name = 'Double' + name
  } else if (repeat == 'triple') {
    name = 'Triple' + name
  }
  name = (button == 1 ? 'Left' : button == 2 ? 'Middle' : 'Right') + name

  return dispatchKey(cm, addModifierNames(name, event), event, function (bound) {
    if (typeof bound === 'string') {
      bound = commands[bound]
    }
    if (!bound) {
      return false
    }
    var done = false
    try {
      if (cm.isReadOnly()) {
        cm.state.suppressEdits = true
      }
      done = bound(cm, pos) != Pass
    } finally {
      cm.state.suppressEdits = false
    }
    return done
  })
}

function configureMouse (cm, repeat, event) {
  var option = cm.getOption('configureMouse')
  var value = option ? option(cm, repeat, event) : {}
  if (value.unit == null) {
    var rect = chromeOS ? event.shiftKey && event.metaKey : event.altKey
    value.unit = rect ? 'rectangle' : repeat == 'single' ? 'char' : repeat == 'double' ? 'word' : 'line'
  }
  if (value.extend == null || cm.doc.extend) {
    value.extend = cm.doc.extend || event.shiftKey
  }
  if (value.addNew == null) {
    value.addNew = mac ? event.metaKey : event.ctrlKey
  }
  if (value.moveOnDrag == null) {
    value.moveOnDrag = !(mac ? event.altKey : event.ctrlKey)
  }
  return value
}

function leftButtonDown (cm, pos, repeat, event) {
  if (ie) {
    setTimeout(bind(ensureFocus, cm), 0)
  } else {
    cm.curOp.focus = activeElt()
  }

  var behavior = configureMouse(cm, repeat, event)

  var sel = cm.doc.sel; var contained
  if (cm.options.dragDrop && dragAndDrop && !cm.isReadOnly() &&
        repeat == 'single' && (contained = sel.contains(pos)) > -1 &&
        (cmp((contained = sel.ranges[contained]).from(), pos) < 0 || pos.xRel > 0) &&
        (cmp(contained.to(), pos) > 0 || pos.xRel < 0)) {
    leftButtonStartDrag(cm, event, pos, behavior)
  } else {
    leftButtonSelect(cm, event, pos, behavior)
  }
}

// Start a text drag. When it ends, see if any dragging actually
// happen, and treat as a click if it didn't.
function leftButtonStartDrag (cm, event, pos, behavior) {
  var display = cm.display; var moved = false
  var dragEnd = operation(cm, function (e) {
    if (webkit) {
      display.scroller.draggable = false
    }
    cm.state.draggingText = false
    off(display.wrapper.ownerDocument, 'mouseup', dragEnd)
    off(display.wrapper.ownerDocument, 'mousemove', mouseMove)
    off(display.scroller, 'dragstart', dragStart)
    off(display.scroller, 'drop', dragEnd)
    if (!moved) {
      e_preventDefault(e)
      if (!behavior.addNew) {
        extendSelection(cm.doc, pos, null, null, behavior.extend)
      }
      // Work around unexplainable focus problem in IE9 (#2127) and Chrome (#3081)
      if (webkit || ie && ie_version == 9) {
        setTimeout(function () {
          display.wrapper.ownerDocument.body.focus()
          display.input.focus()
        }, 20)
      } else {
        display.input.focus()
      }
    }
  })
  var mouseMove = function (e2) {
    moved = moved || Math.abs(event.clientX - e2.clientX) + Math.abs(event.clientY - e2.clientY) >= 10
  }
  var dragStart = function () {
    return moved = true
  }
  // Let the drag handler handle this.
  if (webkit) {
    display.scroller.draggable = true
  }
  cm.state.draggingText = dragEnd
  dragEnd.copy = !behavior.moveOnDrag
  // IE's approach to draggable
  if (display.scroller.dragDrop) {
    display.scroller.dragDrop()
  }
  on(display.wrapper.ownerDocument, 'mouseup', dragEnd)
  on(display.wrapper.ownerDocument, 'mousemove', mouseMove)
  on(display.scroller, 'dragstart', dragStart)
  on(display.scroller, 'drop', dragEnd)

  delayBlurEvent(cm)
  setTimeout(function () {
    return display.input.focus()
  }, 20)
}

function rangeForUnit (cm, pos, unit) {
  if (unit == 'char') {
    return new Range(pos, pos)
  }
  if (unit == 'word') {
    return cm.findWordAt(pos)
  }
  if (unit == 'line') {
    return new Range(Pos(pos.line, 0), clipPos(cm.doc, Pos(pos.line + 1, 0)))
  }
  var result = unit(cm, pos)
  return new Range(result.from, result.to)
}

// Normal selection, as opposed to text dragging.
function leftButtonSelect (cm, event, start, behavior) {
  var display = cm.display; var doc = cm.doc
  e_preventDefault(event)

  var ourRange; var ourIndex; var startSel = doc.sel; var ranges = startSel.ranges
  if (behavior.addNew && !behavior.extend) {
    ourIndex = doc.sel.contains(start)
    if (ourIndex > -1) {
      ourRange = ranges[ourIndex]
    } else {
      ourRange = new Range(start, start)
    }
  } else {
    ourRange = doc.sel.primary()
    ourIndex = doc.sel.primIndex
  }

  if (behavior.unit == 'rectangle') {
    if (!behavior.addNew) {
      ourRange = new Range(start, start)
    }
    start = posFromMouse(cm, event, true, true)
    ourIndex = -1
  } else {
    var range$$1 = rangeForUnit(cm, start, behavior.unit)
    if (behavior.extend) {
      ourRange = extendRange(ourRange, range$$1.anchor, range$$1.head, behavior.extend)
    } else {
      ourRange = range$$1
    }
  }

  if (!behavior.addNew) {
    ourIndex = 0
    setSelection(doc, new Selection([ourRange], 0), sel_mouse)
    startSel = doc.sel
  } else if (ourIndex == -1) {
    ourIndex = ranges.length
    setSelection(doc, normalizeSelection(cm, ranges.concat([ourRange]), ourIndex),
      { scroll: false, origin: '*mouse' })
  } else if (ranges.length > 1 && ranges[ourIndex].empty() && behavior.unit == 'char' && !behavior.extend) {
    setSelection(doc, normalizeSelection(cm, ranges.slice(0, ourIndex).concat(ranges.slice(ourIndex + 1)), 0),
      { scroll: false, origin: '*mouse' })
    startSel = doc.sel
  } else {
    replaceOneSelection(doc, ourIndex, ourRange, sel_mouse)
  }

  var lastPos = start

  function extendTo (pos) {
    if (cmp(lastPos, pos) == 0) {
      return
    }
    lastPos = pos

    if (behavior.unit == 'rectangle') {
      var ranges = []; var tabSize = cm.options.tabSize
      var startCol = countColumn(getLine(doc, start.line).text, start.ch, tabSize)
      var posCol = countColumn(getLine(doc, pos.line).text, pos.ch, tabSize)
      var left = Math.min(startCol, posCol); var right = Math.max(startCol, posCol)
      for (var line = Math.min(start.line, pos.line), end = Math.min(cm.lastLine(), Math.max(start.line, pos.line));
        line <= end; line++) {
        var text = getLine(doc, line).text; var leftPos = findColumn(text, left, tabSize)
        if (left == right) {
          ranges.push(new Range(Pos(line, leftPos), Pos(line, leftPos)))
        } else if (text.length > leftPos) {
          ranges.push(new Range(Pos(line, leftPos), Pos(line, findColumn(text, right, tabSize))))
        }
      }
      if (!ranges.length) {
        ranges.push(new Range(start, start))
      }
      setSelection(doc, normalizeSelection(cm, startSel.ranges.slice(0, ourIndex).concat(ranges), ourIndex),
        { origin: '*mouse', scroll: false })
      cm.scrollIntoView(pos)
    } else {
      var oldRange = ourRange
      var range$$1 = rangeForUnit(cm, pos, behavior.unit)
      var anchor = oldRange.anchor; var head
      if (cmp(range$$1.anchor, anchor) > 0) {
        head = range$$1.head
        anchor = minPos(oldRange.from(), range$$1.anchor)
      } else {
        head = range$$1.anchor
        anchor = maxPos(oldRange.to(), range$$1.head)
      }
      var ranges$1 = startSel.ranges.slice(0)
      ranges$1[ourIndex] = bidiSimplify(cm, new Range(clipPos(doc, anchor), head))
      setSelection(doc, normalizeSelection(cm, ranges$1, ourIndex), sel_mouse)
    }
  }

  var editorSize = display.wrapper.getBoundingClientRect()
  // Used to ensure timeout re-tries don't fire when another extend
  // happened in the meantime (clearTimeout isn't reliable -- at
  // least on Chrome, the timeouts still happen even when cleared,
  // if the clear happens after their scheduled firing time).
  var counter = 0

  function extend (e) {
    var curCount = ++counter
    var cur = posFromMouse(cm, e, true, behavior.unit == 'rectangle')
    if (!cur) {
      return
    }
    if (cmp(cur, lastPos) != 0) {
      cm.curOp.focus = activeElt()
      extendTo(cur)
      var visible = visibleLines(display, doc)
      if (cur.line >= visible.to || cur.line < visible.from) {
        setTimeout(operation(cm, function () {
          if (counter == curCount) {
            extend(e)
          }
        }), 150)
      }
    } else {
      var outside = e.clientY < editorSize.top ? -20 : e.clientY > editorSize.bottom ? 20 : 0
      if (outside) {
        setTimeout(operation(cm, function () {
          if (counter != curCount) {
            return
          }
          display.scroller.scrollTop += outside
          extend(e)
        }), 50)
      }
    }
  }

  function done (e) {
    cm.state.selectingText = false
    counter = Infinity
    // If e is null or undefined we interpret this as someone trying
    // to explicitly cancel the selection rather than the user
    // letting go of the mouse button.
    if (e) {
      e_preventDefault(e)
      display.input.focus()
    }
    off(display.wrapper.ownerDocument, 'mousemove', move)
    off(display.wrapper.ownerDocument, 'mouseup', up)
    doc.history.lastSelOrigin = null
  }

  var move = operation(cm, function (e) {
    if (e.buttons === 0 || !e_button(e)) {
      done(e)
    } else {
      extend(e)
    }
  })
  var up = operation(cm, done)
  cm.state.selectingText = up
  on(display.wrapper.ownerDocument, 'mousemove', move)
  on(display.wrapper.ownerDocument, 'mouseup', up)
}

// Used when mouse-selecting to adjust the anchor to the proper side
// of a bidi jump depending on the visual position of the head.
function bidiSimplify (cm, range$$1) {
  var anchor = range$$1.anchor
  var head = range$$1.head
  var anchorLine = getLine(cm.doc, anchor.line)
  if (cmp(anchor, head) == 0 && anchor.sticky == head.sticky) {
    return range$$1
  }
  var order = getOrder(anchorLine)
  if (!order) {
    return range$$1
  }
  var index = getBidiPartAt(order, anchor.ch, anchor.sticky); var part = order[index]
  if (part.from != anchor.ch && part.to != anchor.ch) {
    return range$$1
  }
  var boundary = index + ((part.from == anchor.ch) == (part.level != 1) ? 0 : 1)
  if (boundary == 0 || boundary == order.length) {
    return range$$1
  }

  // Compute the relative visual position of the head compared to the
  // anchor (<0 is to the left, >0 to the right)
  var leftSide
  if (head.line != anchor.line) {
    leftSide = (head.line - anchor.line) * (cm.doc.direction == 'ltr' ? 1 : -1) > 0
  } else {
    var headIndex = getBidiPartAt(order, head.ch, head.sticky)
    var dir = headIndex - index || (head.ch - anchor.ch) * (part.level == 1 ? -1 : 1)
    if (headIndex == boundary - 1 || headIndex == boundary) {
      leftSide = dir < 0
    } else {
      leftSide = dir > 0
    }
  }

  var usePart = order[boundary + (leftSide ? -1 : 0)]
  var from = leftSide == (usePart.level == 1)
  var ch = from ? usePart.from : usePart.to; var sticky = from ? 'after' : 'before'
  return anchor.ch == ch && anchor.sticky == sticky ? range$$1 : new Range(new Pos(anchor.line, ch, sticky), head)
}

// Determines whether an event happened in the gutter, and fires the
// handlers for the corresponding event.
function gutterEvent (cm, e, type, prevent) {
  var mX, mY
  if (e.touches) {
    mX = e.touches[0].clientX
    mY = e.touches[0].clientY
  } else {
    try {
      mX = e.clientX
      mY = e.clientY
    } catch (e) {
      return false
    }
  }
  if (mX >= Math.floor(cm.display.gutters.getBoundingClientRect().right)) {
    return false
  }
  if (prevent) {
    e_preventDefault(e)
  }

  var display = cm.display
  var lineBox = display.lineDiv.getBoundingClientRect()

  if (mY > lineBox.bottom || !hasHandler(cm, type)) {
    return e_defaultPrevented(e)
  }
  mY -= lineBox.top - display.viewOffset

  for (var i = 0; i < cm.display.gutterSpecs.length; ++i) {
    var g = display.gutters.childNodes[i]
    if (g && g.getBoundingClientRect().right >= mX) {
      var line = lineAtHeight(cm.doc, mY)
      var gutter = cm.display.gutterSpecs[i]
      signal(cm, type, cm, line, gutter.className, e)
      return e_defaultPrevented(e)
    }
  }
}

function clickInGutter (cm, e) {
  return gutterEvent(cm, e, 'gutterClick', true)
}

// CONTEXT MENU HANDLING

// To make the context menu work, we need to briefly unhide the
// textarea (making it as unobtrusive as possible) to let the
// right-click take effect on it.
function onContextMenu (cm, e) {
  if (eventInWidget(cm.display, e) || contextMenuInGutter(cm, e)) {
    return
  }
  if (signalDOMEvent(cm, e, 'contextmenu')) {
    return
  }
  if (!captureRightClick) {
    cm.display.input.onContextMenu(e)
  }
}

function contextMenuInGutter (cm, e) {
  if (!hasHandler(cm, 'gutterContextMenu')) {
    return false
  }
  return gutterEvent(cm, e, 'gutterContextMenu', false)
}

function themeChanged (cm) {
  cm.display.wrapper.className = cm.display.wrapper.className.replace(/\s*cm-s-\S+/g, '') +
        cm.options.theme.replace(/(^|\s)\s*/g, ' cm-s-')
  clearCaches(cm)
}

var Init = {
  toString: function () {
    return 'CodeMirror.Init'
  }
}

var defaults = {}
var optionHandlers = {}

function defineOptions (CodeMirror) {
  var optionHandlers = CodeMirror.optionHandlers

  function option (name, deflt, handle, notOnInit) {
    CodeMirror.defaults[name] = deflt
    if (handle) {
      optionHandlers[name] =
                notOnInit ? function (cm, val, old) {
                  if (old != Init) {
                    handle(cm, val, old)
                  }
                } : handle
    }
  }

  CodeMirror.defineOption = option

  // Passed to option handlers when there is no old value.
  CodeMirror.Init = Init

  // These two are, on init, called from the constructor because they
  // have to be initialized before the src can start at all.
  option('value', '', function (cm, val) {
    return cm.setValue(val)
  }, true)
  option('mode', null, function (cm, val) {
    cm.doc.modeOption = val
    loadMode(cm)
  }, true)

  option('indentUnit', 2, loadMode, true)
  option('indentWithTabs', false)
  option('smartIndent', true)
  option('tabSize', 4, function (cm) {
    resetModeState(cm)
    clearCaches(cm)
    regChange(cm)
  }, true)

  option('lineSeparator', null, function (cm, val) {
    cm.doc.lineSep = val
    if (!val) {
      return
    }
    var newBreaks = []; var lineNo = cm.doc.first
    cm.doc.iter(function (line) {
      for (var pos = 0; ;) {
        var found = line.text.indexOf(val, pos)
        if (found == -1) {
          break
        }
        pos = found + val.length
        newBreaks.push(Pos(lineNo, found))
      }
      lineNo++
    })
    for (var i = newBreaks.length - 1; i >= 0; i--) {
      replaceRange(cm.doc, val, newBreaks[i], Pos(newBreaks[i].line, newBreaks[i].ch + val.length))
    }
  })
  option('specialChars', /[\u0000-\u001f\u007f-\u009f\u00ad\u061c\u200b-\u200f\u2028\u2029\ufeff\ufff9-\ufffc]/g, function (cm, val, old) {
    cm.state.specialChars = new RegExp(val.source + (val.test('\t') ? '' : '|\t'), 'g')
    if (old != Init) {
      cm.refresh()
    }
  })
  option('specialCharPlaceholder', defaultSpecialCharPlaceholder, function (cm) {
    return cm.refresh()
  }, true)
  option('electricChars', true)
  option('inputStyle', mobile ? 'contenteditable' : 'textarea', function () {
    throw new Error('inputStyle can not (yet) be changed in a running src') // FIXME
  }, true)
  option('spellcheck', false, function (cm, val) {
    return cm.getInputField().spellcheck = val
  }, true)
  option('autocorrect', false, function (cm, val) {
    return cm.getInputField().autocorrect = val
  }, true)
  option('autocapitalize', false, function (cm, val) {
    return cm.getInputField().autocapitalize = val
  }, true)
  option('rtlMoveVisually', !windows)
  option('wholeLineUpdateBefore', true)

  option('theme', 'default', function (cm) {
    themeChanged(cm)
    updateGutters(cm)
  }, true)
  option('keyMap', 'default', function (cm, val, old) {
    var next = getKeyMap(val)
    var prev = old != Init && getKeyMap(old)
    if (prev && prev.detach) {
      prev.detach(cm, next)
    }
    if (next.attach) {
      next.attach(cm, prev || null)
    }
  })
  option('extraKeys', null)
  option('configureMouse', null)

  option('lineWrapping', false, wrappingChanged, true)
  option('gutters', [], function (cm, val) {
    cm.display.gutterSpecs = getGutters(val, cm.options.lineNumbers)
    updateGutters(cm)
  }, true)
  option('fixedGutter', true, function (cm, val) {
    cm.display.gutters.style.left = val ? compensateForHScroll(cm.display) + 'px' : '0'
    cm.refresh()
  }, true)
  option('coverGutterNextToScrollbar', false, function (cm) {
    return updateScrollbars(cm)
  }, true)
  option('scrollbarStyle', 'native', function (cm) {
    initScrollbars(cm)
    updateScrollbars(cm)
    cm.display.scrollbars.setScrollTop(cm.doc.scrollTop)
    cm.display.scrollbars.setScrollLeft(cm.doc.scrollLeft)
  }, true)
  option('lineNumbers', false, function (cm, val) {
    cm.display.gutterSpecs = getGutters(cm.options.gutters, val)
    updateGutters(cm)
  }, true)
  option('firstLineNumber', 1, updateGutters, true)
  option('lineNumberFormatter', function (integer) {
    return integer
  }, updateGutters, true)
  option('showCursorWhenSelecting', false, updateSelection, true)

  option('resetSelectionOnContextMenu', true)
  option('lineWiseCopyCut', true)
  option('pasteLinesPerSelection', true)
  option('selectionsMayTouch', false)

  option('readOnly', false, function (cm, val) {
    if (val == 'nocursor') {
      onBlur(cm)
      cm.display.input.blur()
    }
    cm.display.input.readOnlyChanged(val)
  })
  option('disableInput', false, function (cm, val) {
    if (!val) {
      cm.display.input.reset()
    }
  }, true)
  option('dragDrop', true, dragDropChanged)
  option('allowDropFileTypes', null)

  option('cursorBlinkRate', 530)
  option('cursorScrollMargin', 0)
  option('cursorHeight', 1, updateSelection, true)
  option('singleCursorHeightPerLine', true, updateSelection, true)
  option('workTime', 100)
  option('workDelay', 100)
  option('flattenSpans', true, resetModeState, true)
  option('addModeClass', false, resetModeState, true)
  option('pollInterval', 100)
  option('undoDepth', 200, function (cm, val) {
    return cm.doc.history.undoDepth = val
  })
  option('historyEventDelay', 1250)
  option('viewportMargin', 10, function (cm) {
    return cm.refresh()
  }, true)
  option('maxHighlightLength', 10000, resetModeState, true)
  option('moveInputWithCursor', true, function (cm, val) {
    if (!val) {
      cm.display.input.resetPosition()
    }
  })

  option('tabindex', null, function (cm, val) {
    return cm.display.input.getField().tabIndex = val || ''
  })
  option('autofocus', null)
  option('direction', 'ltr', function (cm, val) {
    return cm.doc.setDirection(val)
  }, true)
  option('phrases', null)
}

function dragDropChanged (cm, value, old) {
  var wasOn = old && old != Init
  if (!value != !wasOn) {
    var funcs = cm.display.dragFunctions
    var toggle = value ? on : off
    toggle(cm.display.scroller, 'dragstart', funcs.start)
    toggle(cm.display.scroller, 'dragenter', funcs.enter)
    toggle(cm.display.scroller, 'dragover', funcs.over)
    toggle(cm.display.scroller, 'dragleave', funcs.leave)
    toggle(cm.display.scroller, 'drop', funcs.drop)
  }
}

function wrappingChanged (cm) {
  if (cm.options.lineWrapping) {
    addClass(cm.display.wrapper, 'CodeMirror-wrap')
    cm.display.sizer.style.minWidth = ''
    cm.display.sizerWidth = null
  } else {
    rmClass(cm.display.wrapper, 'CodeMirror-wrap')
    findMaxLine(cm)
  }
  estimateLineHeights(cm)
  regChange(cm)
  clearCaches(cm)
  setTimeout(function () {
    return updateScrollbars(cm)
  }, 100)
}

// A CodeMirror instance represents an src. This is the object
// that user code is usually dealing with.

function CodeMirror (place, options) {
  var this$1 = this

  if (!(this instanceof CodeMirror)) {
    return new CodeMirror(place, options)
  }

  this.options = options = options ? copyObj(options) : {}
  // Determine effective options based on given values and defaults.
  copyObj(defaults, options, false)

  var doc = options.value
  if (typeof doc === 'string') {
    doc = new Doc(doc, options.mode, null, options.lineSeparator, options.direction)
  } else if (options.mode) {
    doc.modeOption = options.mode
  }
  this.doc = doc

  var input = new CodeMirror.inputStyles[options.inputStyle](this)
  var display = this.display = new Display(place, doc, input, options)
  display.wrapper.CodeMirror = this
  themeChanged(this)
  if (options.lineWrapping) {
    this.display.wrapper.className += ' CodeMirror-wrap'
  }
  initScrollbars(this)

  this.state = {
    keyMaps: [], // stores maps added by addKeyMap
    overlays: [], // highlighting overlays, as added by addOverlay
    modeGen: 0, // bumped when mode/overlay changes, used to invalidate highlighting info
    overwrite: false,
    delayingBlurEvent: false,
    focused: false,
    suppressEdits: false, // used to disable editing during key handlers when in readOnly mode
    pasteIncoming: -1,
    cutIncoming: -1, // help recognize paste/cut edits in input.poll
    selectingText: false,
    draggingText: false,
    highlight: new Delayed(), // stores highlight worker timeout
    keySeq: null, // Unfinished key sequence
    specialChars: null
  }

  if (options.autofocus && !mobile) {
    display.input.focus()
  }

  // Override magic textarea content restore that IE sometimes does
  // on our hidden textarea on reload
  if (ie && ie_version < 11) {
    setTimeout(function () {
      return this$1.display.input.reset(true)
    }, 20)
  }

  registerEventHandlers(this)
  ensureGlobalHandlers()

  startOperation(this)
  this.curOp.forceUpdate = true
  attachDoc(this, doc)

  if ((options.autofocus && !mobile) || this.hasFocus()) {
    setTimeout(bind(onFocus, this), 20)
  } else {
    onBlur(this)
  }

  for (var opt in optionHandlers) {
    if (optionHandlers.hasOwnProperty(opt)) {
      optionHandlers[opt](this$1, options[opt], Init)
    }
  }
  maybeUpdateLineNumberWidth(this)
  if (options.finishInit) {
    options.finishInit(this)
  }
  for (var i = 0; i < initHooks.length; ++i) {
    initHooks[i](this$1)
  }
  endOperation(this)
  // Suppress optimizelegibility in Webkit, since it breaks text
  // measuring on line wrapping boundaries.
  if (webkit && options.lineWrapping &&
        getComputedStyle(display.lineDiv).textRendering == 'optimizelegibility') {
    display.lineDiv.style.textRendering = 'auto'
  }
  if (options.onload) {
    options.onload(this)
  }
}

// The default configuration options.
CodeMirror.defaults = defaults
// Functions to run when options are changed.
CodeMirror.optionHandlers = optionHandlers

// Attach the necessary event handlers when initializing the src
function registerEventHandlers (cm) {
  var d = cm.display
  on(d.scroller, 'mousedown', operation(cm, onMouseDown))
  // Older IE's will not fire a second mousedown for a double click
  if (ie && ie_version < 11) {
    on(d.scroller, 'dblclick', operation(cm, function (e) {
      if (signalDOMEvent(cm, e)) {
        return
      }
      var pos = posFromMouse(cm, e)
      if (!pos || clickInGutter(cm, e) || eventInWidget(cm.display, e)) {
        return
      }
      e_preventDefault(e)
      var word = cm.findWordAt(pos)
      extendSelection(cm.doc, word.anchor, word.head)
    }))
  } else {
    on(d.scroller, 'dblclick', function (e) {
      return signalDOMEvent(cm, e) || e_preventDefault(e)
    })
  }
  // Some browsers fire contextmenu *after* opening the menu, at
  // which point we can't mess with it anymore. Context menu is
  // handled in onMouseDown for these browsers.
  on(d.scroller, 'contextmenu', function (e) {
    return onContextMenu(cm, e)
  })

  // Used to suppress mouse event handling when a touch happens
  var touchFinished; var prevTouch = { end: 0 }

  function finishTouch () {
    if (d.activeTouch) {
      touchFinished = setTimeout(function () {
        return d.activeTouch = null
      }, 1000)
      prevTouch = d.activeTouch
      prevTouch.end = +new Date()
    }
  }

  function isMouseLikeTouchEvent (e) {
    if (e.touches.length != 1) {
      return false
    }
    var touch = e.touches[0]
    return touch.radiusX <= 1 && touch.radiusY <= 1
  }

  function farAway (touch, other) {
    if (other.left == null) {
      return true
    }
    var dx = other.left - touch.left; var dy = other.top - touch.top
    return dx * dx + dy * dy > 20 * 20
  }

  on(d.scroller, 'touchstart', function (e) {
    if (!signalDOMEvent(cm, e) && !isMouseLikeTouchEvent(e) && !clickInGutter(cm, e)) {
      d.input.ensurePolled()
      clearTimeout(touchFinished)
      var now = +new Date()
      d.activeTouch = {
        start: now,
        moved: false,
        prev: now - prevTouch.end <= 300 ? prevTouch : null
      }
      if (e.touches.length == 1) {
        d.activeTouch.left = e.touches[0].pageX
        d.activeTouch.top = e.touches[0].pageY
      }
    }
  })
  on(d.scroller, 'touchmove', function () {
    if (d.activeTouch) {
      d.activeTouch.moved = true
    }
  })
  on(d.scroller, 'touchend', function (e) {
    var touch = d.activeTouch
    if (touch && !eventInWidget(d, e) && touch.left != null &&
            !touch.moved && new Date() - touch.start < 300) {
      var pos = cm.coordsChar(d.activeTouch, 'page'); var range
      if (!touch.prev || farAway(touch, touch.prev)) // Single tap
      {
        range = new Range(pos, pos)
      } else if (!touch.prev.prev || farAway(touch, touch.prev.prev)) // Double tap
      {
        range = cm.findWordAt(pos)
      } else // Triple tap
      {
        range = new Range(Pos(pos.line, 0), clipPos(cm.doc, Pos(pos.line + 1, 0)))
      }
      cm.setSelection(range.anchor, range.head)
      cm.focus()
      e_preventDefault(e)
    }
    finishTouch()
  })
  on(d.scroller, 'touchcancel', finishTouch)

  // Sync scrolling between fake scrollbars and real scrollable
  // area, ensure viewport is updated when scrolling.
  on(d.scroller, 'scroll', function () {
    if (d.scroller.clientHeight) {
      updateScrollTop(cm, d.scroller.scrollTop)
      setScrollLeft(cm, d.scroller.scrollLeft, true)
      signal(cm, 'scroll', cm)
    }
  })

  // Listen to wheel events in order to try and update the viewport on time.
  on(d.scroller, 'mousewheel', function (e) {
    return onScrollWheel(cm, e)
  })
  on(d.scroller, 'DOMMouseScroll', function (e) {
    return onScrollWheel(cm, e)
  })

  // Prevent wrapper from ever scrolling
  on(d.wrapper, 'scroll', function () {
    return d.wrapper.scrollTop = d.wrapper.scrollLeft = 0
  })
  d.dragFunctions = {
    enter: function (e) {
      if (!signalDOMEvent(cm, e)) {
        e_stop(e)
      }
    },
    over: function (e) {
      if (!signalDOMEvent(cm, e)) {
        onDragOver(cm, e)
        e_stop(e)
      }
    },
    start: function (e) {
      return onDragStart(cm, e)
    },
    drop: operation(cm, onDrop),
    leave: function (e) {
      if (!signalDOMEvent(cm, e)) {
        clearDragCursor(cm)
      }
    }
  }

  var inp = d.input.getField()
  on(inp, 'keyup', function (e) {
    return onKeyUp.call(cm, e)
  })
  on(inp, 'keydown', operation(cm, onKeyDown))
  on(inp, 'keypress', operation(cm, onKeyPress))
  on(inp, 'focus', function (e) {
    return onFocus(cm, e)
  })
  on(inp, 'blur', function (e) {
    return onBlur(cm, e)
  })
}

var initHooks = []
CodeMirror.defineInitHook = function (f) {
  return initHooks.push(f)
}

// Indent the given line. The how parameter can be "smart",
// "add"/null, "subtract", or "prev". When aggressive is false
// (typically set to true for forced single-line indents), empty
// lines are not indented, and places where the mode returns Pass
// are left alone.
function indentLine (cm, n, how, aggressive) {
  var doc = cm.doc; var state
  if (how == null) {
    how = 'add'
  }
  if (how == 'smart') {
    // Fall back to "prev" when the mode doesn't have an indentation
    // method.
    if (!doc.mode.indent) {
      how = 'prev'
    } else {
      state = getContextBefore(cm, n).state
    }
  }

  var tabSize = cm.options.tabSize
  var line = getLine(doc, n); var curSpace = countColumn(line.text, null, tabSize)
  if (line.stateAfter) {
    line.stateAfter = null
  }
  var curSpaceString = line.text.match(/^\s*/)[0]; var indentation
  if (!aggressive && !/\S/.test(line.text)) {
    indentation = 0
    how = 'not'
  } else if (how == 'smart') {
    indentation = doc.mode.indent(state, line.text.slice(curSpaceString.length), line.text)
    if (indentation == Pass || indentation > 150) {
      if (!aggressive) {
        return
      }
      how = 'prev'
    }
  }
  if (how == 'prev') {
    if (n > doc.first) {
      indentation = countColumn(getLine(doc, n - 1).text, null, tabSize)
    } else {
      indentation = 0
    }
  } else if (how == 'add') {
    indentation = curSpace + cm.options.indentUnit
  } else if (how == 'subtract') {
    indentation = curSpace - cm.options.indentUnit
  } else if (typeof how === 'number') {
    indentation = curSpace + how
  }
  indentation = Math.max(0, indentation)

  var indentString = ''; var pos = 0
  if (cm.options.indentWithTabs) {
    for (var i = Math.floor(indentation / tabSize); i; --i) {
      pos += tabSize
      indentString += '\t'
    }
  }
  if (pos < indentation) {
    indentString += spaceStr(indentation - pos)
  }

  if (indentString != curSpaceString) {
    replaceRange(doc, indentString, Pos(n, 0), Pos(n, curSpaceString.length), '+input')
    line.stateAfter = null
    return true
  } else {
    // Ensure that, if the cursor was in the whitespace at the start
    // of the line, it is moved to the end of that space.
    for (var i$1 = 0; i$1 < doc.sel.ranges.length; i$1++) {
      var range = doc.sel.ranges[i$1]
      if (range.head.line == n && range.head.ch < curSpaceString.length) {
        var pos$1 = Pos(n, curSpaceString.length)
        replaceOneSelection(doc, i$1, new Range(pos$1, pos$1))
        break
      }
    }
  }
}

// This will be set to a {lineWise: bool, text: [string]} object, so
// that, when pasting, we know what kind of selections the copied
// text was made out of.
var lastCopied = null

function setLastCopied (newLastCopied) {
  lastCopied = newLastCopied
}

function applyTextInput (cm, inserted, deleted, sel, origin) {
  var doc = cm.doc
  cm.display.shift = false
  if (!sel) {
    sel = doc.sel
  }

  var recent = +new Date() - 200
  var paste = origin == 'paste' || cm.state.pasteIncoming > recent
  var textLines = splitLinesAuto(inserted); var multiPaste = null
  // When pasting N lines into N selections, insert one line per selection
  if (paste && sel.ranges.length > 1) {
    if (lastCopied && lastCopied.text.join('\n') == inserted) {
      if (sel.ranges.length % lastCopied.text.length == 0) {
        multiPaste = []
        for (var i = 0; i < lastCopied.text.length; i++) {
          multiPaste.push(doc.splitLines(lastCopied.text[i]))
        }
      }
    } else if (textLines.length == sel.ranges.length && cm.options.pasteLinesPerSelection) {
      multiPaste = map(textLines, function (l) {
        return [l]
      })
    }
  }

  var updateInput = cm.curOp.updateInput
  // Normal behavior is to insert the new text into every selection
  for (var i$1 = sel.ranges.length - 1; i$1 >= 0; i$1--) {
    var range$$1 = sel.ranges[i$1]
    var from = range$$1.from(); var to = range$$1.to()
    if (range$$1.empty()) {
      if (deleted && deleted > 0) // Handle deletion
      {
        from = Pos(from.line, from.ch - deleted)
      } else if (cm.state.overwrite && !paste) // Handle overwrite
      {
        to = Pos(to.line, Math.min(getLine(doc, to.line).text.length, to.ch + lst(textLines).length))
      } else if (paste && lastCopied && lastCopied.lineWise && lastCopied.text.join('\n') == inserted) {
        from = to = Pos(from.line, 0)
      }
    }
    var changeEvent = {
      from: from,
      to: to,
      text: multiPaste ? multiPaste[i$1 % multiPaste.length] : textLines,
      origin: origin || (paste ? 'paste' : cm.state.cutIncoming > recent ? 'cut' : '+input')
    }
    makeChange(cm.doc, changeEvent)
    signalLater(cm, 'inputRead', cm, changeEvent)
  }
  if (inserted && !paste) {
    triggerElectric(cm, inserted)
  }

  ensureCursorVisible(cm)
  if (cm.curOp.updateInput < 2) {
    cm.curOp.updateInput = updateInput
  }
  cm.curOp.typing = true
  cm.state.pasteIncoming = cm.state.cutIncoming = -1
}

function handlePaste (e, cm) {
  var pasted = e.clipboardData && e.clipboardData.getData('Text')
  if (pasted) {
    e.preventDefault()
    if (!cm.isReadOnly() && !cm.options.disableInput) {
      runInOp(cm, function () {
        return applyTextInput(cm, pasted, 0, null, 'paste')
      })
    }
    return true
  }
}

function triggerElectric (cm, inserted) {
  // When an 'electric' character is inserted, immediately trigger a reindent
  if (!cm.options.electricChars || !cm.options.smartIndent) {
    return
  }
  var sel = cm.doc.sel

  for (var i = sel.ranges.length - 1; i >= 0; i--) {
    var range$$1 = sel.ranges[i]
    if (range$$1.head.ch > 100 || (i && sel.ranges[i - 1].head.line == range$$1.head.line)) {
      continue
    }
    var mode = cm.getModeAt(range$$1.head)
    var indented = false
    if (mode.electricChars) {
      for (var j = 0; j < mode.electricChars.length; j++) {
        if (inserted.indexOf(mode.electricChars.charAt(j)) > -1) {
          indented = indentLine(cm, range$$1.head.line, 'smart')
          break
        }
      }
    } else if (mode.electricInput) {
      if (mode.electricInput.test(getLine(cm.doc, range$$1.head.line).text.slice(0, range$$1.head.ch))) {
        indented = indentLine(cm, range$$1.head.line, 'smart')
      }
    }
    if (indented) {
      signalLater(cm, 'electricInput', cm, range$$1.head.line)
    }
  }
}

function copyableRanges (cm) {
  var text = []; var ranges = []
  for (var i = 0; i < cm.doc.sel.ranges.length; i++) {
    var line = cm.doc.sel.ranges[i].head.line
    var lineRange = { anchor: Pos(line, 0), head: Pos(line + 1, 0) }
    ranges.push(lineRange)
    text.push(cm.getRange(lineRange.anchor, lineRange.head))
  }
  return { text: text, ranges: ranges }
}

function disableBrowserMagic (field, spellcheck, autocorrect, autocapitalize) {
  field.setAttribute('autocorrect', autocorrect ? '' : 'off')
  field.setAttribute('autocapitalize', autocapitalize ? '' : 'off')
  field.setAttribute('spellcheck', !!spellcheck)
}

function hiddenTextarea () {
  var te = elt('textarea', null, null, 'position: absolute; bottom: -1em; padding: 0; width: 1px; height: 1em; outline: none')
  var div = elt('div', [te], null, 'overflow: hidden; position: relative; width: 3px; height: 0px;')
  // The textarea is kept positioned near the cursor to prevent the
  // fact that it'll be scrolled into view on input from scrolling
  // our fake cursor out of view. On webkit, when wrap=off, paste is
  // very slow. So make the area wide instead.
  if (webkit) {
    te.style.width = '1000px'
  } else {
    te.setAttribute('wrap', 'off')
  }
  // If border: 0; -- iOS fails to open keyboard (issue #1287)
  if (ios) {
    te.style.border = '1px solid black'
  }
  disableBrowserMagic(te)
  return div
}

// The publicly visible API. Note that methodOp(f) means
// 'wrap f in an operation, performed on its `this` parameter'.

// This is not the complete set of src methods. Most of the
// methods defined on the Doc type are also injected into
// CodeMirror.prototype, for backwards compatibility and
// convenience.

function addEditorMethods (CodeMirror) {
  var optionHandlers = CodeMirror.optionHandlers

  var helpers = CodeMirror.helpers = {}

  CodeMirror.prototype = {
    constructor: CodeMirror,
    focus: function () {
      window.focus()
      this.display.input.focus()
    },

    setOption: function (option, value) {
      var options = this.options; var old = options[option]
      if (options[option] == value && option != 'mode') {
        return
      }
      options[option] = value
      if (optionHandlers.hasOwnProperty(option)) {
        operation(this, optionHandlers[option])(this, value, old)
      }
      signal(this, 'optionChange', this, option)
    },

    getOption: function (option) {
      return this.options[option]
    },
    getDoc: function () {
      return this.doc
    },

    addKeyMap: function (map$$1, bottom) {
      this.state.keyMaps[bottom ? 'push' : 'unshift'](getKeyMap(map$$1))
    },
    removeKeyMap: function (map$$1) {
      var maps = this.state.keyMaps
      for (var i = 0; i < maps.length; ++i) {
        if (maps[i] == map$$1 || maps[i].name == map$$1) {
          maps.splice(i, 1)
          return true
        }
      }
    },

    addOverlay: methodOp(function (spec, options) {
      var mode = spec.token ? spec : CodeMirror.getMode(this.options, spec)
      if (mode.startState) {
        throw new Error('Overlays may not be stateful.')
      }
      insertSorted(this.state.overlays,
        {
          mode: mode,
          modeSpec: spec,
          opaque: options && options.opaque,
          priority: (options && options.priority) || 0
        },
        function (overlay) {
          return overlay.priority
        })
      this.state.modeGen++
      regChange(this)
    }),
    removeOverlay: methodOp(function (spec) {
      var this$1 = this

      var overlays = this.state.overlays
      for (var i = 0; i < overlays.length; ++i) {
        var cur = overlays[i].modeSpec
        if (cur == spec || typeof spec === 'string' && cur.name == spec) {
          overlays.splice(i, 1)
          this$1.state.modeGen++
          regChange(this$1)
          return
        }
      }
    }),

    indentLine: methodOp(function (n, dir, aggressive) {
      if (typeof dir !== 'string' && typeof dir !== 'number') {
        if (dir == null) {
          dir = this.options.smartIndent ? 'smart' : 'prev'
        } else {
          dir = dir ? 'add' : 'subtract'
        }
      }
      if (isLine(this.doc, n)) {
        indentLine(this, n, dir, aggressive)
      }
    }),
    indentSelection: methodOp(function (how) {
      var this$1 = this

      var ranges = this.doc.sel.ranges; var end = -1
      for (var i = 0; i < ranges.length; i++) {
        var range$$1 = ranges[i]
        if (!range$$1.empty()) {
          var from = range$$1.from(); var to = range$$1.to()
          var start = Math.max(end, from.line)
          end = Math.min(this$1.lastLine(), to.line - (to.ch ? 0 : 1)) + 1
          for (var j = start; j < end; ++j) {
            indentLine(this$1, j, how)
          }
          var newRanges = this$1.doc.sel.ranges
          if (from.ch == 0 && ranges.length == newRanges.length && newRanges[i].from().ch > 0) {
            replaceOneSelection(this$1.doc, i, new Range(from, newRanges[i].to()), sel_dontScroll)
          }
        } else if (range$$1.head.line > end) {
          indentLine(this$1, range$$1.head.line, how, true)
          end = range$$1.head.line
          if (i == this$1.doc.sel.primIndex) {
            ensureCursorVisible(this$1)
          }
        }
      }
    }),

    // Fetch the parser token for a given character. Useful for hacks
    // that want to inspect the mode state (say, for completion).
    getTokenAt: function (pos, precise) {
      return takeToken(this, pos, precise)
    },

    getLineTokens: function (line, precise) {
      return takeToken(this, Pos(line), precise, true)
    },

    getTokenTypeAt: function (pos) {
      pos = clipPos(this.doc, pos)
      var styles = getLineStyles(this, getLine(this.doc, pos.line))
      var before = 0; var after = (styles.length - 1) / 2; var ch = pos.ch
      var type
      if (ch == 0) {
        type = styles[2]
      } else {
        for (; ;) {
          var mid = (before + after) >> 1
          if ((mid ? styles[mid * 2 - 1] : 0) >= ch) {
            after = mid
          } else if (styles[mid * 2 + 1] < ch) {
            before = mid + 1
          } else {
            type = styles[mid * 2 + 2]
            break
          }
        }
      }
      var cut = type ? type.indexOf('overlay ') : -1
      return cut < 0 ? type : cut == 0 ? null : type.slice(0, cut - 1)
    },

    getModeAt: function (pos) {
      var mode = this.doc.mode
      if (!mode.innerMode) {
        return mode
      }
      return CodeMirror.innerMode(mode, this.getTokenAt(pos).state).mode
    },

    getHelper: function (pos, type) {
      return this.getHelpers(pos, type)[0]
    },

    getHelpers: function (pos, type) {
      var this$1 = this

      var found = []
      if (!helpers.hasOwnProperty(type)) {
        return found
      }
      var help = helpers[type]; var mode = this.getModeAt(pos)
      if (typeof mode[type] === 'string') {
        if (help[mode[type]]) {
          found.push(help[mode[type]])
        }
      } else if (mode[type]) {
        for (var i = 0; i < mode[type].length; i++) {
          var val = help[mode[type][i]]
          if (val) {
            found.push(val)
          }
        }
      } else if (mode.helperType && help[mode.helperType]) {
        found.push(help[mode.helperType])
      } else if (help[mode.name]) {
        found.push(help[mode.name])
      }
      for (var i$1 = 0; i$1 < help._global.length; i$1++) {
        var cur = help._global[i$1]
        if (cur.pred(mode, this$1) && indexOf(found, cur.val) == -1) {
          found.push(cur.val)
        }
      }
      return found
    },

    getStateAfter: function (line, precise) {
      var doc = this.doc
      line = clipLine(doc, line == null ? doc.first + doc.size - 1 : line)
      return getContextBefore(this, line + 1, precise).state
    },

    cursorCoords: function (start, mode) {
      var pos; var range$$1 = this.doc.sel.primary()
      if (start == null) {
        pos = range$$1.head
      } else if (typeof start === 'object') {
        pos = clipPos(this.doc, start)
      } else {
        pos = start ? range$$1.from() : range$$1.to()
      }
      return cursorCoords(this, pos, mode || 'page')
    },

    charCoords: function (pos, mode) {
      return charCoords(this, clipPos(this.doc, pos), mode || 'page')
    },

    coordsChar: function (coords, mode) {
      coords = fromCoordSystem(this, coords, mode || 'page')
      return coordsChar(this, coords.left, coords.top)
    },

    lineAtHeight: function (height, mode) {
      height = fromCoordSystem(this, { top: height, left: 0 }, mode || 'page').top
      return lineAtHeight(this.doc, height + this.display.viewOffset)
    },
    heightAtLine: function (line, mode, includeWidgets) {
      var end = false; var lineObj
      if (typeof line === 'number') {
        var last = this.doc.first + this.doc.size - 1
        if (line < this.doc.first) {
          line = this.doc.first
        } else if (line > last) {
          line = last
          end = true
        }
        lineObj = getLine(this.doc, line)
      } else {
        lineObj = line
      }
      return intoCoordSystem(this, lineObj, { top: 0, left: 0 }, mode || 'page', includeWidgets || end).top +
                (end ? this.doc.height - heightAtLine(lineObj) : 0)
    },

    defaultTextHeight: function () {
      return textHeight(this.display)
    },
    defaultCharWidth: function () {
      return charWidth(this.display)
    },

    getViewport: function () {
      return { from: this.display.viewFrom, to: this.display.viewTo }
    },

    addWidget: function (pos, node, scroll, vert, horiz) {
      var display = this.display
      pos = cursorCoords(this, clipPos(this.doc, pos))
      var top = pos.bottom; var left = pos.left
      node.style.position = 'absolute'
      node.setAttribute('cm-ignore-events', 'true')
      this.display.input.setUneditable(node)
      display.sizer.appendChild(node)
      if (vert == 'over') {
        top = pos.top
      } else if (vert == 'above' || vert == 'near') {
        var vspace = Math.max(display.wrapper.clientHeight, this.doc.height)
        var hspace = Math.max(display.sizer.clientWidth, display.lineSpace.clientWidth)
        // Default to positioning above (if specified and possible); otherwise default to positioning below
        if ((vert == 'above' || pos.bottom + node.offsetHeight > vspace) && pos.top > node.offsetHeight) {
          top = pos.top - node.offsetHeight
        } else if (pos.bottom + node.offsetHeight <= vspace) {
          top = pos.bottom
        }
        if (left + node.offsetWidth > hspace) {
          left = hspace - node.offsetWidth
        }
      }
      node.style.top = top + 'px'
      node.style.left = node.style.right = ''
      if (horiz == 'right') {
        left = display.sizer.clientWidth - node.offsetWidth
        node.style.right = '0px'
      } else {
        if (horiz == 'left') {
          left = 0
        } else if (horiz == 'middle') {
          left = (display.sizer.clientWidth - node.offsetWidth) / 2
        }
        node.style.left = left + 'px'
      }
      if (scroll) {
        scrollIntoView(this, {
          left: left,
          top: top,
          right: left + node.offsetWidth,
          bottom: top + node.offsetHeight
        })
      }
    },

    triggerOnKeyDown: methodOp(onKeyDown),
    triggerOnKeyPress: methodOp(onKeyPress),
    triggerOnKeyUp: onKeyUp,
    triggerOnMouseDown: methodOp(onMouseDown),

    execCommand: function (cmd) {
      if (commands.hasOwnProperty(cmd)) {
        return commands[cmd].call(null, this)
      }
    },

    triggerElectric: methodOp(function (text) {
      triggerElectric(this, text)
    }),

    findPosH: function (from, amount, unit, visually) {
      var this$1 = this

      var dir = 1
      if (amount < 0) {
        dir = -1
        amount = -amount
      }
      var cur = clipPos(this.doc, from)
      for (var i = 0; i < amount; ++i) {
        cur = findPosH(this$1.doc, cur, dir, unit, visually)
        if (cur.hitSide) {
          break
        }
      }
      return cur
    },

    moveH: methodOp(function (dir, unit) {
      var this$1 = this

      this.extendSelectionsBy(function (range$$1) {
        if (this$1.display.shift || this$1.doc.extend || range$$1.empty()) {
          return findPosH(this$1.doc, range$$1.head, dir, unit, this$1.options.rtlMoveVisually)
        } else {
          return dir < 0 ? range$$1.from() : range$$1.to()
        }
      }, sel_move)
    }),

    deleteH: methodOp(function (dir, unit) {
      var sel = this.doc.sel; var doc = this.doc
      if (sel.somethingSelected()) {
        doc.replaceSelection('', null, '+delete')
      } else {
        deleteNearSelection(this, function (range$$1) {
          var other = findPosH(doc, range$$1.head, dir, unit, false)
          return dir < 0 ? { from: other, to: range$$1.head } : { from: range$$1.head, to: other }
        })
      }
    }),

    findPosV: function (from, amount, unit, goalColumn) {
      var this$1 = this

      var dir = 1; var x = goalColumn
      if (amount < 0) {
        dir = -1
        amount = -amount
      }
      var cur = clipPos(this.doc, from)
      for (var i = 0; i < amount; ++i) {
        var coords = cursorCoords(this$1, cur, 'div')
        if (x == null) {
          x = coords.left
        } else {
          coords.left = x
        }
        cur = findPosV(this$1, coords, dir, unit)
        if (cur.hitSide) {
          break
        }
      }
      return cur
    },

    moveV: methodOp(function (dir, unit) {
      var this$1 = this

      var doc = this.doc; var goals = []
      var collapse = !this.display.shift && !doc.extend && doc.sel.somethingSelected()
      doc.extendSelectionsBy(function (range$$1) {
        if (collapse) {
          return dir < 0 ? range$$1.from() : range$$1.to()
        }
        var headPos = cursorCoords(this$1, range$$1.head, 'div')
        if (range$$1.goalColumn != null) {
          headPos.left = range$$1.goalColumn
        }
        goals.push(headPos.left)
        var pos = findPosV(this$1, headPos, dir, unit)
        if (unit == 'page' && range$$1 == doc.sel.primary()) {
          addToScrollTop(this$1, charCoords(this$1, pos, 'div').top - headPos.top)
        }
        return pos
      }, sel_move)
      if (goals.length) {
        for (var i = 0; i < doc.sel.ranges.length; i++) {
          doc.sel.ranges[i].goalColumn = goals[i]
        }
      }
    }),

    // Find the word at the given position (as returned by coordsChar).
    findWordAt: function (pos) {
      var doc = this.doc; var line = getLine(doc, pos.line).text
      var start = pos.ch; var end = pos.ch
      if (line) {
        var helper = this.getHelper(pos, 'wordChars')
        if ((pos.sticky == 'before' || end == line.length) && start) {
          --start
        } else {
          ++end
        }
        var startChar = line.charAt(start)
        var check = isWordChar(startChar, helper)
          ? function (ch) {
            return isWordChar(ch, helper)
          }
          : /\s/.test(startChar) ? function (ch) {
            return /\s/.test(ch)
          }
            : function (ch) {
              return (!/\s/.test(ch) && !isWordChar(ch))
            }
        while (start > 0 && check(line.charAt(start - 1))) {
          --start
        }
        while (end < line.length && check(line.charAt(end))) {
          ++end
        }
      }
      return new Range(Pos(pos.line, start), Pos(pos.line, end))
    },

    toggleOverwrite: function (value) {
      if (value != null && value == this.state.overwrite) {
        return
      }
      if (this.state.overwrite = !this.state.overwrite) {
        addClass(this.display.cursorDiv, 'CodeMirror-overwrite')
      } else {
        rmClass(this.display.cursorDiv, 'CodeMirror-overwrite')
      }

      signal(this, 'overwriteToggle', this, this.state.overwrite)
    },
    hasFocus: function () {
      return this.display.input.getField() == activeElt()
    },
    isReadOnly: function () {
      return !!(this.options.readOnly || this.doc.cantEdit)
    },

    scrollTo: methodOp(function (x, y) {
      scrollToCoords(this, x, y)
    }),
    getScrollInfo: function () {
      var scroller = this.display.scroller
      return {
        left: scroller.scrollLeft,
        top: scroller.scrollTop,
        height: scroller.scrollHeight - scrollGap(this) - this.display.barHeight,
        width: scroller.scrollWidth - scrollGap(this) - this.display.barWidth,
        clientHeight: displayHeight(this),
        clientWidth: displayWidth(this)
      }
    },

    scrollIntoView: methodOp(function (range$$1, margin) {
      if (range$$1 == null) {
        range$$1 = { from: this.doc.sel.primary().head, to: null }
        if (margin == null) {
          margin = this.options.cursorScrollMargin
        }
      } else if (typeof range$$1 === 'number') {
        range$$1 = { from: Pos(range$$1, 0), to: null }
      } else if (range$$1.from == null) {
        range$$1 = { from: range$$1, to: null }
      }
      if (!range$$1.to) {
        range$$1.to = range$$1.from
      }
      range$$1.margin = margin || 0

      if (range$$1.from.line != null) {
        scrollToRange(this, range$$1)
      } else {
        scrollToCoordsRange(this, range$$1.from, range$$1.to, range$$1.margin)
      }
    }),

    setSize: methodOp(function (width, height) {
      var this$1 = this

      var interpret = function (val) {
        return typeof val === 'number' || /^\d+$/.test(String(val)) ? val + 'px' : val
      }
      if (width != null) {
        this.display.wrapper.style.width = interpret(width)
      }
      if (height != null) {
        this.display.wrapper.style.height = interpret(height)
      }
      if (this.options.lineWrapping) {
        clearLineMeasurementCache(this)
      }
      var lineNo$$1 = this.display.viewFrom
      this.doc.iter(lineNo$$1, this.display.viewTo, function (line) {
        if (line.widgets) {
          for (var i = 0; i < line.widgets.length; i++) {
            if (line.widgets[i].noHScroll) {
              regLineChange(this$1, lineNo$$1, 'widget')
              break
            }
          }
        }
        ++lineNo$$1
      })
      this.curOp.forceUpdate = true
      signal(this, 'refresh', this)
    }),

    operation: function (f) {
      return runInOp(this, f)
    },
    startOperation: function () {
      return startOperation(this)
    },
    endOperation: function () {
      return endOperation(this)
    },

    refresh: methodOp(function () {
      var oldHeight = this.display.cachedTextHeight
      regChange(this)
      this.curOp.forceUpdate = true
      clearCaches(this)
      scrollToCoords(this, this.doc.scrollLeft, this.doc.scrollTop)
      updateGutterSpace(this.display)
      if (oldHeight == null || Math.abs(oldHeight - textHeight(this.display)) > 0.5) {
        estimateLineHeights(this)
      }
      signal(this, 'refresh', this)
    }),

    swapDoc: methodOp(function (doc) {
      var old = this.doc
      old.cm = null
      // Cancel the current text selection if any (#5821)
      if (this.state.selectingText) {
        this.state.selectingText()
      }
      attachDoc(this, doc)
      clearCaches(this)
      this.display.input.reset()
      scrollToCoords(this, doc.scrollLeft, doc.scrollTop)
      this.curOp.forceScroll = true
      signalLater(this, 'swapDoc', this, old)
      return old
    }),

    phrase: function (phraseText) {
      var phrases = this.options.phrases
      return phrases && Object.prototype.hasOwnProperty.call(phrases, phraseText) ? phrases[phraseText] : phraseText
    },

    getInputField: function () {
      return this.display.input.getField()
    },
    getWrapperElement: function () {
      return this.display.wrapper
    },
    getScrollerElement: function () {
      return this.display.scroller
    },
    getGutterElement: function () {
      return this.display.gutters
    }
  }
  eventMixin(CodeMirror)

  CodeMirror.registerHelper = function (type, name, value) {
    if (!helpers.hasOwnProperty(type)) {
      helpers[type] = CodeMirror[type] = { _global: [] }
    }
    helpers[type][name] = value
  }
  CodeMirror.registerGlobalHelper = function (type, name, predicate, value) {
    CodeMirror.registerHelper(type, name, value)
    helpers[type]._global.push({ pred: predicate, val: value })
  }
}

// Used for horizontal relative motion. Dir is -1 or 1 (left or
// right), unit can be "char", "column" (like char, but doesn't
// cross line boundaries), "word" (across next word), or "group" (to
// the start of next group of word or non-word-non-whitespace
// chars). The visually param controls whether, in right-to-left
// text, direction 1 means to move towards the next index in the
// string, or towards the character to the right of the current
// position. The resulting position will have a hitSide=true
// property if it reached the end of the document.
function findPosH (doc, pos, dir, unit, visually) {
  var oldPos = pos
  var origDir = dir
  var lineObj = getLine(doc, pos.line)

  function findNextLine () {
    var l = pos.line + dir
    if (l < doc.first || l >= doc.first + doc.size) {
      return false
    }
    pos = new Pos(l, pos.ch, pos.sticky)
    return lineObj = getLine(doc, l)
  }

  function moveOnce (boundToLine) {
    var next
    if (visually) {
      next = moveVisually(doc.cm, lineObj, pos, dir)
    } else {
      next = moveLogically(lineObj, pos, dir)
    }
    if (next == null) {
      if (!boundToLine && findNextLine()) {
        pos = endOfLine(visually, doc.cm, lineObj, pos.line, dir)
      } else {
        return false
      }
    } else {
      pos = next
    }
    return true
  }

  if (unit == 'char') {
    moveOnce()
  } else if (unit == 'column') {
    moveOnce(true)
  } else if (unit == 'word' || unit == 'group') {
    var sawType = null; var group = unit == 'group'
    var helper = doc.cm && doc.cm.getHelper(pos, 'wordChars')
    for (var first = true; ; first = false) {
      if (dir < 0 && !moveOnce(!first)) {
        break
      }
      var cur = lineObj.text.charAt(pos.ch) || '\n'
      var type = isWordChar(cur, helper) ? 'w'
        : group && cur == '\n' ? 'n'
          : !group || /\s/.test(cur) ? null
            : 'p'
      if (group && !first && !type) {
        type = 's'
      }
      if (sawType && sawType != type) {
        if (dir < 0) {
          dir = 1
          moveOnce()
          pos.sticky = 'after'
        }
        break
      }

      if (type) {
        sawType = type
      }
      if (dir > 0 && !moveOnce(!first)) {
        break
      }
    }
  }
  var result = skipAtomic(doc, pos, oldPos, origDir, true)
  if (equalCursorPos(oldPos, result)) {
    result.hitSide = true
  }
  return result
}

// For relative vertical movement. Dir may be -1 or 1. Unit can be
// "page" or "line". The resulting position will have a hitSide=true
// property if it reached the end of the document.
function findPosV (cm, pos, dir, unit) {
  var doc = cm.doc; var x = pos.left; var y
  if (unit == 'page') {
    var pageSize = Math.min(cm.display.wrapper.clientHeight, window.innerHeight || document.documentElement.clientHeight)
    var moveAmount = Math.max(pageSize - 0.5 * textHeight(cm.display), 3)
    y = (dir > 0 ? pos.bottom : pos.top) + dir * moveAmount
  } else if (unit == 'line') {
    y = dir > 0 ? pos.bottom + 3 : pos.top - 3
  }
  var target
  for (; ;) {
    target = coordsChar(cm, x, y)
    if (!target.outside) {
      break
    }
    if (dir < 0 ? y <= 0 : y >= doc.height) {
      target.hitSide = true
      break
    }
    y += dir * 5
  }
  return target
}

// CONTENTEDITABLE INPUT STYLE

var ContentEditableInput = function (cm) {
  this.cm = cm
  this.lastAnchorNode = this.lastAnchorOffset = this.lastFocusNode = this.lastFocusOffset = null
  this.polling = new Delayed()
  this.composing = null
  this.gracePeriod = false
  this.readDOMTimeout = null
}

ContentEditableInput.prototype.init = function (display) {
  var this$1 = this

  var input = this; var cm = input.cm
  var div = input.div = display.lineDiv
  disableBrowserMagic(div, cm.options.spellcheck, cm.options.autocorrect, cm.options.autocapitalize)

  on(div, 'paste', function (e) {
    if (signalDOMEvent(cm, e) || handlePaste(e, cm)) {
      return
    }
    // IE doesn't fire input events, so we schedule a read for the pasted content in this way
    if (ie_version <= 11) {
      setTimeout(operation(cm, function () {
        return this$1.updateFromDOM()
      }), 20)
    }
  })

  on(div, 'compositionstart', function (e) {
    this$1.composing = { data: e.data, done: false }
  })
  on(div, 'compositionupdate', function (e) {
    if (!this$1.composing) {
      this$1.composing = { data: e.data, done: false }
    }
  })
  on(div, 'compositionend', function (e) {
    if (this$1.composing) {
      if (e.data != this$1.composing.data) {
        this$1.readFromDOMSoon()
      }
      this$1.composing.done = true
    }
  })

  on(div, 'touchstart', function () {
    return input.forceCompositionEnd()
  })

  on(div, 'input', function () {
    if (!this$1.composing) {
      this$1.readFromDOMSoon()
    }
  })

  function onCopyCut (e) {
    if (signalDOMEvent(cm, e)) {
      return
    }
    if (cm.somethingSelected()) {
      setLastCopied({ lineWise: false, text: cm.getSelections() })
      if (e.type == 'cut') {
        cm.replaceSelection('', null, 'cut')
      }
    } else if (!cm.options.lineWiseCopyCut) {
      return
    } else {
      var ranges = copyableRanges(cm)
      setLastCopied({ lineWise: true, text: ranges.text })
      if (e.type == 'cut') {
        cm.operation(function () {
          cm.setSelections(ranges.ranges, 0, sel_dontScroll)
          cm.replaceSelection('', null, 'cut')
        })
      }
    }
    if (e.clipboardData) {
      e.clipboardData.clearData()
      var content = lastCopied.text.join('\n')
      // iOS exposes the clipboard API, but seems to discard content inserted into it
      e.clipboardData.setData('Text', content)
      if (e.clipboardData.getData('Text') == content) {
        e.preventDefault()
        return
      }
    }
    // Old-fashioned briefly-focus-a-textarea hack
    var kludge = hiddenTextarea(); var te = kludge.firstChild
    cm.display.lineSpace.insertBefore(kludge, cm.display.lineSpace.firstChild)
    te.value = lastCopied.text.join('\n')
    var hadFocus = document.activeElement
    selectInput(te)
    setTimeout(function () {
      cm.display.lineSpace.removeChild(kludge)
      hadFocus.focus()
      if (hadFocus == div) {
        input.showPrimarySelection()
      }
    }, 50)
  }

  on(div, 'copy', onCopyCut)
  on(div, 'cut', onCopyCut)
}

ContentEditableInput.prototype.prepareSelection = function () {
  var result = prepareSelection(this.cm, false)
  result.focus = this.cm.state.focused
  return result
}

ContentEditableInput.prototype.showSelection = function (info, takeFocus) {
  if (!info || !this.cm.display.view.length) {
    return
  }
  if (info.focus || takeFocus) {
    this.showPrimarySelection()
  }
  this.showMultipleSelections(info)
}

ContentEditableInput.prototype.getSelection = function () {
  return this.cm.display.wrapper.ownerDocument.getSelection()
}

ContentEditableInput.prototype.showPrimarySelection = function () {
  var sel = this.getSelection(); var cm = this.cm; var prim = cm.doc.sel.primary()
  var from = prim.from(); var to = prim.to()

  if (cm.display.viewTo == cm.display.viewFrom || from.line >= cm.display.viewTo || to.line < cm.display.viewFrom) {
    sel.removeAllRanges()
    return
  }

  var curAnchor = domToPos(cm, sel.anchorNode, sel.anchorOffset)
  var curFocus = domToPos(cm, sel.focusNode, sel.focusOffset)
  if (curAnchor && !curAnchor.bad && curFocus && !curFocus.bad &&
        cmp(minPos(curAnchor, curFocus), from) == 0 &&
        cmp(maxPos(curAnchor, curFocus), to) == 0) {
    return
  }

  var view = cm.display.view
  var start = (from.line >= cm.display.viewFrom && posToDOM(cm, from)) ||
        { node: view[0].measure.map[2], offset: 0 }
  var end = to.line < cm.display.viewTo && posToDOM(cm, to)
  if (!end) {
    var measure = view[view.length - 1].measure
    var map$$1 = measure.maps ? measure.maps[measure.maps.length - 1] : measure.map
    end = { node: map$$1[map$$1.length - 1], offset: map$$1[map$$1.length - 2] - map$$1[map$$1.length - 3] }
  }

  if (!start || !end) {
    sel.removeAllRanges()
    return
  }

  var old = sel.rangeCount && sel.getRangeAt(0); var rng
  try {
    rng = range(start.node, start.offset, end.offset, end.node)
  } catch (e) {
  } // Our model of the DOM might be outdated, in which case the range we try to set can be impossible
  if (rng) {
    if (!gecko && cm.state.focused) {
      sel.collapse(start.node, start.offset)
      if (!rng.collapsed) {
        sel.removeAllRanges()
        sel.addRange(rng)
      }
    } else {
      sel.removeAllRanges()
      sel.addRange(rng)
    }
    if (old && sel.anchorNode == null) {
      sel.addRange(old)
    } else if (gecko) {
      this.startGracePeriod()
    }
  }
  this.rememberSelection()
}

ContentEditableInput.prototype.startGracePeriod = function () {
  var this$1 = this

  clearTimeout(this.gracePeriod)
  this.gracePeriod = setTimeout(function () {
    this$1.gracePeriod = false
    if (this$1.selectionChanged()) {
      this$1.cm.operation(function () {
        return this$1.cm.curOp.selectionChanged = true
      })
    }
  }, 20)
}

ContentEditableInput.prototype.showMultipleSelections = function (info) {
  removeChildrenAndAdd(this.cm.display.cursorDiv, info.cursors)
  removeChildrenAndAdd(this.cm.display.selectionDiv, info.selection)
}

ContentEditableInput.prototype.rememberSelection = function () {
  var sel = this.getSelection()
  this.lastAnchorNode = sel.anchorNode
  this.lastAnchorOffset = sel.anchorOffset
  this.lastFocusNode = sel.focusNode
  this.lastFocusOffset = sel.focusOffset
}

ContentEditableInput.prototype.selectionInEditor = function () {
  var sel = this.getSelection()
  if (!sel.rangeCount) {
    return false
  }
  var node = sel.getRangeAt(0).commonAncestorContainer
  return contains(this.div, node)
}

ContentEditableInput.prototype.focus = function () {
  if (this.cm.options.readOnly != 'nocursor') {
    if (!this.selectionInEditor()) {
      this.showSelection(this.prepareSelection(), true)
    }
    this.div.focus()
  }
}
ContentEditableInput.prototype.blur = function () {
  this.div.blur()
}
ContentEditableInput.prototype.getField = function () {
  return this.div
}

ContentEditableInput.prototype.supportsTouch = function () {
  return true
}

ContentEditableInput.prototype.receivedFocus = function () {
  var input = this
  if (this.selectionInEditor()) {
    this.pollSelection()
  } else {
    runInOp(this.cm, function () {
      return input.cm.curOp.selectionChanged = true
    })
  }

  function poll () {
    if (input.cm.state.focused) {
      input.pollSelection()
      input.polling.set(input.cm.options.pollInterval, poll)
    }
  }

  this.polling.set(this.cm.options.pollInterval, poll)
}

ContentEditableInput.prototype.selectionChanged = function () {
  var sel = this.getSelection()
  return sel.anchorNode != this.lastAnchorNode || sel.anchorOffset != this.lastAnchorOffset ||
        sel.focusNode != this.lastFocusNode || sel.focusOffset != this.lastFocusOffset
}

ContentEditableInput.prototype.pollSelection = function () {
  if (this.readDOMTimeout != null || this.gracePeriod || !this.selectionChanged()) {
    return
  }
  var sel = this.getSelection(); var cm = this.cm
  // On Android Chrome (version 56, at least), backspacing into an
  // uneditable block element will put the cursor in that element,
  // and then, because it's not editable, hide the virtual keyboard.
  // Because Android doesn't allow us to actually detect backspace
  // presses in a sane way, this code checks for when that happens
  // and simulates a backspace press in this case.
  if (android && chrome && this.cm.display.gutterSpecs.length && isInGutter(sel.anchorNode)) {
    this.cm.triggerOnKeyDown({ type: 'keydown', keyCode: 8, preventDefault: Math.abs })
    this.blur()
    this.focus()
    return
  }
  if (this.composing) {
    return
  }
  this.rememberSelection()
  var anchor = domToPos(cm, sel.anchorNode, sel.anchorOffset)
  var head = domToPos(cm, sel.focusNode, sel.focusOffset)
  if (anchor && head) {
    runInOp(cm, function () {
      setSelection(cm.doc, simpleSelection(anchor, head), sel_dontScroll)
      if (anchor.bad || head.bad) {
        cm.curOp.selectionChanged = true
      }
    })
  }
}

ContentEditableInput.prototype.pollContent = function () {
  if (this.readDOMTimeout != null) {
    clearTimeout(this.readDOMTimeout)
    this.readDOMTimeout = null
  }

  var cm = this.cm; var display = cm.display; var sel = cm.doc.sel.primary()
  var from = sel.from(); var to = sel.to()
  if (from.ch == 0 && from.line > cm.firstLine()) {
    from = Pos(from.line - 1, getLine(cm.doc, from.line - 1).length)
  }
  if (to.ch == getLine(cm.doc, to.line).text.length && to.line < cm.lastLine()) {
    to = Pos(to.line + 1, 0)
  }
  if (from.line < display.viewFrom || to.line > display.viewTo - 1) {
    return false
  }

  var fromIndex, fromLine, fromNode
  if (from.line == display.viewFrom || (fromIndex = findViewIndex(cm, from.line)) == 0) {
    fromLine = lineNo(display.view[0].line)
    fromNode = display.view[0].node
  } else {
    fromLine = lineNo(display.view[fromIndex].line)
    fromNode = display.view[fromIndex - 1].node.nextSibling
  }
  var toIndex = findViewIndex(cm, to.line)
  var toLine, toNode
  if (toIndex == display.view.length - 1) {
    toLine = display.viewTo - 1
    toNode = display.lineDiv.lastChild
  } else {
    toLine = lineNo(display.view[toIndex + 1].line) - 1
    toNode = display.view[toIndex + 1].node.previousSibling
  }

  if (!fromNode) {
    return false
  }
  var newText = cm.doc.splitLines(domTextBetween(cm, fromNode, toNode, fromLine, toLine))
  var oldText = getBetween(cm.doc, Pos(fromLine, 0), Pos(toLine, getLine(cm.doc, toLine).text.length))
  while (newText.length > 1 && oldText.length > 1) {
    if (lst(newText) == lst(oldText)) {
      newText.pop()
      oldText.pop()
      toLine--
    } else if (newText[0] == oldText[0]) {
      newText.shift()
      oldText.shift()
      fromLine++
    } else {
      break
    }
  }

  var cutFront = 0; var cutEnd = 0
  var newTop = newText[0]; var oldTop = oldText[0]; var maxCutFront = Math.min(newTop.length, oldTop.length)
  while (cutFront < maxCutFront && newTop.charCodeAt(cutFront) == oldTop.charCodeAt(cutFront)) {
    ++cutFront
  }
  var newBot = lst(newText); var oldBot = lst(oldText)
  var maxCutEnd = Math.min(newBot.length - (newText.length == 1 ? cutFront : 0),
    oldBot.length - (oldText.length == 1 ? cutFront : 0))
  while (cutEnd < maxCutEnd &&
    newBot.charCodeAt(newBot.length - cutEnd - 1) == oldBot.charCodeAt(oldBot.length - cutEnd - 1)) {
    ++cutEnd
  }
  // Try to move start of change to start of selection if ambiguous
  if (newText.length == 1 && oldText.length == 1 && fromLine == from.line) {
    while (cutFront && cutFront > from.ch &&
        newBot.charCodeAt(newBot.length - cutEnd - 1) == oldBot.charCodeAt(oldBot.length - cutEnd - 1)) {
      cutFront--
      cutEnd++
    }
  }

  newText[newText.length - 1] = newBot.slice(0, newBot.length - cutEnd).replace(/^\u200b+/, '')
  newText[0] = newText[0].slice(cutFront).replace(/\u200b+$/, '')

  var chFrom = Pos(fromLine, cutFront)
  var chTo = Pos(toLine, oldText.length ? lst(oldText).length - cutEnd : 0)
  if (newText.length > 1 || newText[0] || cmp(chFrom, chTo)) {
    replaceRange(cm.doc, newText, chFrom, chTo, '+input')
    return true
  }
}

ContentEditableInput.prototype.ensurePolled = function () {
  this.forceCompositionEnd()
}
ContentEditableInput.prototype.reset = function () {
  this.forceCompositionEnd()
}
ContentEditableInput.prototype.forceCompositionEnd = function () {
  if (!this.composing) {
    return
  }
  clearTimeout(this.readDOMTimeout)
  this.composing = null
  this.updateFromDOM()
  this.div.blur()
  this.div.focus()
}
ContentEditableInput.prototype.readFromDOMSoon = function () {
  var this$1 = this

  if (this.readDOMTimeout != null) {
    return
  }
  this.readDOMTimeout = setTimeout(function () {
    this$1.readDOMTimeout = null
    if (this$1.composing) {
      if (this$1.composing.done) {
        this$1.composing = null
      } else {
        return
      }
    }
    this$1.updateFromDOM()
  }, 80)
}

ContentEditableInput.prototype.updateFromDOM = function () {
  var this$1 = this

  if (this.cm.isReadOnly() || !this.pollContent()) {
    runInOp(this.cm, function () {
      return regChange(this$1.cm)
    })
  }
}

ContentEditableInput.prototype.setUneditable = function (node) {
  node.contentEditable = 'false'
}

ContentEditableInput.prototype.onKeyPress = function (e) {
  if (e.charCode == 0 || this.composing) {
    return
  }
  e.preventDefault()
  if (!this.cm.isReadOnly()) {
    operation(this.cm, applyTextInput)(this.cm, String.fromCharCode(e.charCode == null ? e.keyCode : e.charCode), 0)
  }
}

ContentEditableInput.prototype.readOnlyChanged = function (val) {
  this.div.contentEditable = String(val != 'nocursor')
}

ContentEditableInput.prototype.onContextMenu = function () {
}
ContentEditableInput.prototype.resetPosition = function () {
}

ContentEditableInput.prototype.needsContentAttribute = true

function posToDOM (cm, pos) {
  var view = findViewForLine(cm, pos.line)
  if (!view || view.hidden) {
    return null
  }
  var line = getLine(cm.doc, pos.line)
  var info = mapFromLineView(view, line, pos.line)

  var order = getOrder(line, cm.doc.direction); var side = 'left'
  if (order) {
    var partPos = getBidiPartAt(order, pos.ch)
    side = partPos % 2 ? 'right' : 'left'
  }
  var result = nodeAndOffsetInLineMap(info.map, pos.ch, side)
  result.offset = result.collapse == 'right' ? result.end : result.start
  return result
}

function isInGutter (node) {
  for (var scan = node; scan; scan = scan.parentNode) {
    if (/CodeMirror-gutter-wrapper/.test(scan.className)) {
      return true
    }
  }
  return false
}

function badPos (pos, bad) {
  if (bad) {
    pos.bad = true
  }
  return pos
}

function domTextBetween (cm, from, to, fromLine, toLine) {
  var text = ''; var closing = false; var lineSep = cm.doc.lineSeparator(); var extraLinebreak = false

  function recognizeMarker (id) {
    return function (marker) {
      return marker.id == id
    }
  }

  function close () {
    if (closing) {
      text += lineSep
      if (extraLinebreak) {
        text += lineSep
      }
      closing = extraLinebreak = false
    }
  }

  function addText (str) {
    if (str) {
      close()
      text += str
    }
  }

  function walk (node) {
    if (node.nodeType == 1) {
      var cmText = node.getAttribute('cm-text')
      if (cmText) {
        addText(cmText)
        return
      }
      var markerID = node.getAttribute('cm-marker'); var range$$1
      if (markerID) {
        var found = cm.findMarks(Pos(fromLine, 0), Pos(toLine + 1, 0), recognizeMarker(+markerID))
        if (found.length && (range$$1 = found[0].find(0))) {
          addText(getBetween(cm.doc, range$$1.from, range$$1.to).join(lineSep))
        }
        return
      }
      if (node.getAttribute('contenteditable') == 'false') {
        return
      }
      var isBlock = /^(pre|div|p|li|table|br)$/i.test(node.nodeName)
      if (!/^br$/i.test(node.nodeName) && node.textContent.length == 0) {
        return
      }

      if (isBlock) {
        close()
      }
      for (var i = 0; i < node.childNodes.length; i++) {
        walk(node.childNodes[i])
      }

      if (/^(pre|p)$/i.test(node.nodeName)) {
        extraLinebreak = true
      }
      if (isBlock) {
        closing = true
      }
    } else if (node.nodeType == 3) {
      addText(node.nodeValue.replace(/\u200b/g, '').replace(/\u00a0/g, ' '))
    }
  }

  for (; ;) {
    walk(from)
    if (from == to) {
      break
    }
    from = from.nextSibling
    extraLinebreak = false
  }
  return text
}

function domToPos (cm, node, offset) {
  var lineNode
  if (node == cm.display.lineDiv) {
    lineNode = cm.display.lineDiv.childNodes[offset]
    if (!lineNode) {
      return badPos(cm.clipPos(Pos(cm.display.viewTo - 1)), true)
    }
    node = null
    offset = 0
  } else {
    for (lineNode = node; ; lineNode = lineNode.parentNode) {
      if (!lineNode || lineNode == cm.display.lineDiv) {
        return null
      }
      if (lineNode.parentNode && lineNode.parentNode == cm.display.lineDiv) {
        break
      }
    }
  }
  for (var i = 0; i < cm.display.view.length; i++) {
    var lineView = cm.display.view[i]
    if (lineView.node == lineNode) {
      return locateNodeInLineView(lineView, node, offset)
    }
  }
}

function locateNodeInLineView (lineView, node, offset) {
  var wrapper = lineView.text.firstChild; var bad = false
  if (!node || !contains(wrapper, node)) {
    return badPos(Pos(lineNo(lineView.line), 0), true)
  }
  if (node == wrapper) {
    bad = true
    node = wrapper.childNodes[offset]
    offset = 0
    if (!node) {
      var line = lineView.rest ? lst(lineView.rest) : lineView.line
      return badPos(Pos(lineNo(line), line.text.length), bad)
    }
  }

  var textNode = node.nodeType == 3 ? node : null; var topNode = node
  if (!textNode && node.childNodes.length == 1 && node.firstChild.nodeType == 3) {
    textNode = node.firstChild
    if (offset) {
      offset = textNode.nodeValue.length
    }
  }
  while (topNode.parentNode != wrapper) {
    topNode = topNode.parentNode
  }
  var measure = lineView.measure; var maps = measure.maps

  function find (textNode, topNode, offset) {
    for (var i = -1; i < (maps ? maps.length : 0); i++) {
      var map$$1 = i < 0 ? measure.map : maps[i]
      for (var j = 0; j < map$$1.length; j += 3) {
        var curNode = map$$1[j + 2]
        if (curNode == textNode || curNode == topNode) {
          var line = lineNo(i < 0 ? lineView.line : lineView.rest[i])
          var ch = map$$1[j] + offset
          if (offset < 0 || curNode != textNode) {
            ch = map$$1[j + (offset ? 1 : 0)]
          }
          return Pos(line, ch)
        }
      }
    }
  }

  var found = find(textNode, topNode, offset)
  if (found) {
    return badPos(found, bad)
  }

  // FIXME this is all really shaky. might handle the few cases it needs to handle, but likely to cause problems
  for (var after = topNode.nextSibling, dist = textNode ? textNode.nodeValue.length - offset : 0; after; after = after.nextSibling) {
    found = find(after, after.firstChild, 0)
    if (found) {
      return badPos(Pos(found.line, found.ch - dist), bad)
    } else {
      dist += after.textContent.length
    }
  }
  for (var before = topNode.previousSibling, dist$1 = offset; before; before = before.previousSibling) {
    found = find(before, before.firstChild, -1)
    if (found) {
      return badPos(Pos(found.line, found.ch + dist$1), bad)
    } else {
      dist$1 += before.textContent.length
    }
  }
}

// TEXTAREA INPUT STYLE

var TextareaInput = function (cm) {
  this.cm = cm
  // See input.poll and input.reset
  this.prevInput = ''

  // Flag that indicates whether we expect input to appear real soon
  // now (after some event like 'keypress' or 'input') and are
  // polling intensively.
  this.pollingFast = false
  // Self-resetting timeout for the poller
  this.polling = new Delayed()
  // Used to work around IE issue with selection being forgotten when focus moves away from textarea
  this.hasSelection = false
  this.composing = null
}

TextareaInput.prototype.init = function (display) {
  var this$1 = this

  var input = this; var cm = this.cm
  this.createField(display)
  var te = this.textarea

  display.wrapper.insertBefore(this.wrapper, display.wrapper.firstChild)

  // Needed to hide big blue blinking cursor on Mobile Safari (doesn't seem to work in iOS 8 anymore)
  if (ios) {
    te.style.width = '0px'
  }

  on(te, 'input', function () {
    if (ie && ie_version >= 9 && this$1.hasSelection) {
      this$1.hasSelection = null
    }
    input.poll()
  })

  on(te, 'paste', function (e) {
    if (signalDOMEvent(cm, e) || handlePaste(e, cm)) {
      return
    }

    cm.state.pasteIncoming = +new Date()
    input.fastPoll()
  })

  function prepareCopyCut (e) {
    if (signalDOMEvent(cm, e)) {
      return
    }
    if (cm.somethingSelected()) {
      setLastCopied({ lineWise: false, text: cm.getSelections() })
    } else if (!cm.options.lineWiseCopyCut) {
      return
    } else {
      var ranges = copyableRanges(cm)
      setLastCopied({ lineWise: true, text: ranges.text })
      if (e.type == 'cut') {
        cm.setSelections(ranges.ranges, null, sel_dontScroll)
      } else {
        input.prevInput = ''
        te.value = ranges.text.join('\n')
        selectInput(te)
      }
    }
    if (e.type == 'cut') {
      cm.state.cutIncoming = +new Date()
    }
  }

  on(te, 'cut', prepareCopyCut)
  on(te, 'copy', prepareCopyCut)

  on(display.scroller, 'paste', function (e) {
    if (eventInWidget(display, e) || signalDOMEvent(cm, e)) {
      return
    }
    if (!te.dispatchEvent) {
      cm.state.pasteIncoming = +new Date()
      input.focus()
      return
    }

    // Pass the `paste` event to the textarea so it's handled by its event listener.
    var event = new Event('paste')
    event.clipboardData = e.clipboardData
    te.dispatchEvent(event)
  })

  // Prevent normal selection in the src (we handle our own)
  on(display.lineSpace, 'selectstart', function (e) {
    if (!eventInWidget(display, e)) {
      e_preventDefault(e)
    }
  })

  on(te, 'compositionstart', function () {
    var start = cm.getCursor('from')
    if (input.composing) {
      input.composing.range.clear()
    }
    input.composing = {
      start: start,
      range: cm.markText(start, cm.getCursor('to'), { className: 'CodeMirror-composing' })
    }
  })
  on(te, 'compositionend', function () {
    if (input.composing) {
      input.poll()
      input.composing.range.clear()
      input.composing = null
    }
  })
}

TextareaInput.prototype.createField = function (_display) {
  // Wraps and hides input textarea
  this.wrapper = hiddenTextarea()
  // The semihidden textarea that is focused when the src is
  // focused, and receives input.
  this.textarea = this.wrapper.firstChild
}

TextareaInput.prototype.prepareSelection = function () {
  // Redraw the selection and/or cursor
  var cm = this.cm; var display = cm.display; var doc = cm.doc
  var result = prepareSelection(cm)

  // Move the hidden textarea near the cursor to prevent scrolling artifacts
  if (cm.options.moveInputWithCursor) {
    var headPos = cursorCoords(cm, doc.sel.primary().head, 'div')
    var wrapOff = display.wrapper.getBoundingClientRect(); var lineOff = display.lineDiv.getBoundingClientRect()
    result.teTop = Math.max(0, Math.min(display.wrapper.clientHeight - 10,
      headPos.top + lineOff.top - wrapOff.top))
    result.teLeft = Math.max(0, Math.min(display.wrapper.clientWidth - 10,
      headPos.left + lineOff.left - wrapOff.left))
  }

  return result
}

TextareaInput.prototype.showSelection = function (drawn) {
  var cm = this.cm; var display = cm.display
  removeChildrenAndAdd(display.cursorDiv, drawn.cursors)
  removeChildrenAndAdd(display.selectionDiv, drawn.selection)
  if (drawn.teTop != null) {
    this.wrapper.style.top = drawn.teTop + 'px'
    this.wrapper.style.left = drawn.teLeft + 'px'
  }
}

// Reset the input to correspond to the selection (or to be empty,
// when not typing and nothing is selected)
TextareaInput.prototype.reset = function (typing) {
  if (this.contextMenuPending || this.composing) {
    return
  }
  var cm = this.cm
  if (cm.somethingSelected()) {
    this.prevInput = ''
    var content = cm.getSelection()
    this.textarea.value = content
    if (cm.state.focused) {
      selectInput(this.textarea)
    }
    if (ie && ie_version >= 9) {
      this.hasSelection = content
    }
  } else if (!typing) {
    this.prevInput = this.textarea.value = ''
    if (ie && ie_version >= 9) {
      this.hasSelection = null
    }
  }
}

TextareaInput.prototype.getField = function () {
  return this.textarea
}

TextareaInput.prototype.supportsTouch = function () {
  return false
}

TextareaInput.prototype.focus = function () {
  if (this.cm.options.readOnly != 'nocursor' && (!mobile || activeElt() != this.textarea)) {
    try {
      this.textarea.focus()
    } catch (e) {
    } // IE8 will throw if the textarea is display: none or not in DOM
  }
}

TextareaInput.prototype.blur = function () {
  this.textarea.blur()
}

TextareaInput.prototype.resetPosition = function () {
  this.wrapper.style.top = this.wrapper.style.left = 0
}

TextareaInput.prototype.receivedFocus = function () {
  this.slowPoll()
}

// Poll for input changes, using the normal rate of polling. This
// runs as long as the src is focused.
TextareaInput.prototype.slowPoll = function () {
  var this$1 = this

  if (this.pollingFast) {
    return
  }
  this.polling.set(this.cm.options.pollInterval, function () {
    this$1.poll()
    if (this$1.cm.state.focused) {
      this$1.slowPoll()
    }
  })
}

// When an event has just come in that is likely to add or change
// something in the input textarea, we poll faster, to ensure that
// the change appears on the screen quickly.
TextareaInput.prototype.fastPoll = function () {
  var missed = false; var input = this
  input.pollingFast = true

  function p () {
    var changed = input.poll()
    if (!changed && !missed) {
      missed = true
      input.polling.set(60, p)
    } else {
      input.pollingFast = false
      input.slowPoll()
    }
  }

  input.polling.set(20, p)
}

// Read input from the textarea, and update the document to match.
// When something is selected, it is present in the textarea, and
// selected (unless it is huge, in which case a placeholder is
// used). When nothing is selected, the cursor sits after previously
// seen text (can be empty), which is stored in prevInput (we must
// not reset the textarea when typing, because that breaks IME).
TextareaInput.prototype.poll = function () {
  var this$1 = this

  var cm = this.cm; var input = this.textarea; var prevInput = this.prevInput
  // Since this is called a *lot*, try to bail out as cheaply as
  // possible when it is clear that nothing happened. hasSelection
  // will be the case when there is a lot of text in the textarea,
  // in which case reading its value would be expensive.
  if (this.contextMenuPending || !cm.state.focused ||
        (hasSelection(input) && !prevInput && !this.composing) ||
        cm.isReadOnly() || cm.options.disableInput || cm.state.keySeq) {
    return false
  }

  var text = input.value
  // If nothing changed, bail.
  if (text == prevInput && !cm.somethingSelected()) {
    return false
  }
  // Work around nonsensical selection resetting in IE9/10, and
  // inexplicable appearance of private area unicode characters on
  // some key combos in Mac (#2689).
  if (ie && ie_version >= 9 && this.hasSelection === text ||
        mac && /[\uf700-\uf7ff]/.test(text)) {
    cm.display.input.reset()
    return false
  }

  if (cm.doc.sel == cm.display.selForContextMenu) {
    var first = text.charCodeAt(0)
    if (first == 0x200b && !prevInput) {
      prevInput = '\u200b'
    }
    if (first == 0x21da) {
      this.reset()
      return this.cm.execCommand('undo')
    }
  }
  // Find the part of the input that is actually new
  var same = 0; var l = Math.min(prevInput.length, text.length)
  while (same < l && prevInput.charCodeAt(same) == text.charCodeAt(same)) {
    ++same
  }

  runInOp(cm, function () {
    applyTextInput(cm, text.slice(same), prevInput.length - same,
      null, this$1.composing ? '*compose' : null)

    // Don't leave long text in the textarea, since it makes further polling slow
    if (text.length > 1000 || text.indexOf('\n') > -1) {
      input.value = this$1.prevInput = ''
    } else {
      this$1.prevInput = text
    }

    if (this$1.composing) {
      this$1.composing.range.clear()
      this$1.composing.range = cm.markText(this$1.composing.start, cm.getCursor('to'),
        { className: 'CodeMirror-composing' })
    }
  })
  return true
}

TextareaInput.prototype.ensurePolled = function () {
  if (this.pollingFast && this.poll()) {
    this.pollingFast = false
  }
}

TextareaInput.prototype.onKeyPress = function () {
  if (ie && ie_version >= 9) {
    this.hasSelection = null
  }
  this.fastPoll()
}

TextareaInput.prototype.onContextMenu = function (e) {
  var input = this; var cm = input.cm; var display = cm.display; var te = input.textarea
  if (input.contextMenuPending) {
    input.contextMenuPending()
  }
  var pos = posFromMouse(cm, e); var scrollPos = display.scroller.scrollTop
  if (!pos || presto) {
    return
  } // Opera is difficult.

  // Reset the current text selection only if the click is done outside of the selection
  // and 'resetSelectionOnContextMenu' option is true.
  var reset = cm.options.resetSelectionOnContextMenu
  if (reset && cm.doc.sel.contains(pos) == -1) {
    operation(cm, setSelection)(cm.doc, simpleSelection(pos), sel_dontScroll)
  }

  var oldCSS = te.style.cssText; var oldWrapperCSS = input.wrapper.style.cssText
  var wrapperBox = input.wrapper.offsetParent.getBoundingClientRect()
  input.wrapper.style.cssText = 'position: static'
  te.style.cssText = 'position: absolute; width: 30px; height: 30px;\n      top: ' + (e.clientY - wrapperBox.top - 5) + 'px; left: ' + (e.clientX - wrapperBox.left - 5) + 'px;\n      z-index: 1000; background: ' + (ie ? 'rgba(255, 255, 255, .05)' : 'transparent') + ';\n      outline: none; border-width: 0; outline: none; overflow: hidden; opacity: .05; filter: alpha(opacity=5);'
  var oldScrollY
  if (webkit) {
    oldScrollY = window.scrollY
  } // Work around Chrome issue (#2712)
  display.input.focus()
  if (webkit) {
    window.scrollTo(null, oldScrollY)
  }
  display.input.reset()
  // Adds "Select all" to context menu in FF
  if (!cm.somethingSelected()) {
    te.value = input.prevInput = ' '
  }
  input.contextMenuPending = rehide
  display.selForContextMenu = cm.doc.sel
  clearTimeout(display.detectingSelectAll)

  // Select-all will be greyed out if there's nothing to select, so
  // this adds a zero-width space so that we can later check whether
  // it got selected.
  function prepareSelectAllHack () {
    if (te.selectionStart != null) {
      var selected = cm.somethingSelected()
      var extval = '\u200b' + (selected ? te.value : '')
      te.value = '\u21da' // Used to catch context-menu undo
      te.value = extval
      input.prevInput = selected ? '' : '\u200b'
      te.selectionStart = 1
      te.selectionEnd = extval.length
      // Re-set this, in case some other handler touched the
      // selection in the meantime.
      display.selForContextMenu = cm.doc.sel
    }
  }

  function rehide () {
    if (input.contextMenuPending != rehide) {
      return
    }
    input.contextMenuPending = false
    input.wrapper.style.cssText = oldWrapperCSS
    te.style.cssText = oldCSS
    if (ie && ie_version < 9) {
      display.scrollbars.setScrollTop(display.scroller.scrollTop = scrollPos)
    }

    // Try to detect the user choosing select-all
    if (te.selectionStart != null) {
      if (!ie || (ie && ie_version < 9)) {
        prepareSelectAllHack()
      }
      var i = 0; var poll = function () {
        if (display.selForContextMenu == cm.doc.sel && te.selectionStart == 0 &&
                    te.selectionEnd > 0 && input.prevInput == '\u200b') {
          operation(cm, selectAll)(cm)
        } else if (i++ < 10) {
          display.detectingSelectAll = setTimeout(poll, 500)
        } else {
          display.selForContextMenu = null
          display.input.reset()
        }
      }
      display.detectingSelectAll = setTimeout(poll, 200)
    }
  }

  if (ie && ie_version >= 9) {
    prepareSelectAllHack()
  }
  if (captureRightClick) {
    e_stop(e)
    var mouseup = function () {
      off(window, 'mouseup', mouseup)
      setTimeout(rehide, 20)
    }
    on(window, 'mouseup', mouseup)
  } else {
    setTimeout(rehide, 50)
  }
}

TextareaInput.prototype.readOnlyChanged = function (val) {
  if (!val) {
    this.reset()
  }
  this.textarea.disabled = val == 'nocursor'
}

TextareaInput.prototype.setUneditable = function () {
}

TextareaInput.prototype.needsContentAttribute = false

function fromTextArea (textarea, options) {
  options = options ? copyObj(options) : {}
  options.value = textarea.value
  if (!options.tabindex && textarea.tabIndex) {
    options.tabindex = textarea.tabIndex
  }
  if (!options.placeholder && textarea.placeholder) {
    options.placeholder = textarea.placeholder
  }
  // Set autofocus to true if this textarea is focused, or if it has
  // autofocus and no other element is focused.
  if (options.autofocus == null) {
    var hasFocus = activeElt()
    options.autofocus = hasFocus == textarea ||
            textarea.getAttribute('autofocus') != null && hasFocus == document.body
  }

  function save () {
    textarea.value = cm.getValue()
  }

  var realSubmit
  if (textarea.form) {
    on(textarea.form, 'submit', save)
    // Deplorable hack to make the submit method do the right thing.
    if (!options.leaveSubmitMethodAlone) {
      var form = textarea.form
      realSubmit = form.submit
      try {
        var wrappedSubmit = form.submit = function () {
          save()
          form.submit = realSubmit
          form.submit()
          form.submit = wrappedSubmit
        }
      } catch (e) {
      }
    }
  }

  options.finishInit = function (cm) {
    cm.save = save
    cm.getTextArea = function () {
      return textarea
    }
    cm.toTextArea = function () {
      cm.toTextArea = isNaN // Prevent this from being ran twice
      save()
      textarea.parentNode.removeChild(cm.getWrapperElement())
      textarea.style.display = ''
      if (textarea.form) {
        off(textarea.form, 'submit', save)
        if (!options.leaveSubmitMethodAlone && typeof textarea.form.submit === 'function') {
          textarea.form.submit = realSubmit
        }
      }
    }
  }

  textarea.style.display = 'none'
  var cm = CodeMirror(function (node) {
    return textarea.parentNode.insertBefore(node, textarea.nextSibling)
  },
  options)
  return cm
}

function addLegacyProps (CodeMirror) {
  CodeMirror.off = off
  CodeMirror.on = on
  CodeMirror.wheelEventPixels = wheelEventPixels
  CodeMirror.Doc = Doc
  CodeMirror.splitLines = splitLinesAuto
  CodeMirror.countColumn = countColumn
  CodeMirror.findColumn = findColumn
  CodeMirror.isWordChar = isWordCharBasic
  CodeMirror.Pass = Pass
  CodeMirror.signal = signal
  CodeMirror.Line = Line
  CodeMirror.changeEnd = changeEnd
  CodeMirror.scrollbarModel = scrollbarModel
  CodeMirror.Pos = Pos
  CodeMirror.cmpPos = cmp
  CodeMirror.modes = modes
  CodeMirror.mimeModes = mimeModes
  CodeMirror.resolveMode = resolveMode
  CodeMirror.getMode = getMode
  CodeMirror.modeExtensions = modeExtensions
  CodeMirror.extendMode = extendMode
  CodeMirror.copyState = copyState
  CodeMirror.startState = startState
  CodeMirror.innerMode = innerMode
  CodeMirror.commands = commands
  CodeMirror.keyMap = keyMap
  CodeMirror.keyName = keyName
  CodeMirror.isModifierKey = isModifierKey
  CodeMirror.lookupKey = lookupKey
  CodeMirror.normalizeKeyMap = normalizeKeyMap
  CodeMirror.StringStream = StringStream
  CodeMirror.SharedTextMarker = SharedTextMarker
  CodeMirror.TextMarker = TextMarker
  CodeMirror.LineWidget = LineWidget
  CodeMirror.e_preventDefault = e_preventDefault
  CodeMirror.e_stopPropagation = e_stopPropagation
  CodeMirror.e_stop = e_stop
  CodeMirror.addClass = addClass
  CodeMirror.contains = contains
  CodeMirror.rmClass = rmClass
  // CodeMirror.keyNames = keyNames;
}

// EDITOR CONSTRUCTOR

defineOptions(CodeMirror)

addEditorMethods(CodeMirror)

// Set up methods on CodeMirror's prototype to redirect to the src's document.
var dontDelegate = 'iter insert remove copy getEditor constructor'.split(' ')
for (var prop in Doc.prototype) {
  if (Doc.prototype.hasOwnProperty(prop) && indexOf(dontDelegate, prop) < 0) {
    CodeMirror.prototype[prop] = (function (method) {
      return function () {
        return method.apply(this.doc, arguments)
      }
    })(Doc.prototype[prop])
  }
}

eventMixin(Doc)
CodeMirror.inputStyles = { textarea: TextareaInput, contenteditable: ContentEditableInput }

// Extra arguments are stored as the mode's dependencies, which is
// used by (legacy) mechanisms like loadmode.js to automatically
// load a mode. (Preferred mechanism is the require/define calls.)
CodeMirror.defineMode = function (name/*, mode, … */) {
  if (!CodeMirror.defaults.mode && name != 'null') {
    CodeMirror.defaults.mode = name
  }
  defineMode.apply(this, arguments)
}

CodeMirror.defineMIME = defineMIME

// Minimal default mode.
CodeMirror.defineMode('null', function () {
  return ({
    token: function (stream) {
      return stream.skipToEnd()
    }
  })
})
CodeMirror.defineMIME('text/plain', 'null')

// EXTENSIONS

CodeMirror.defineExtension = function (name, func) {
  CodeMirror.prototype[name] = func
}
CodeMirror.defineDocExtension = function (name, func) {
  Doc.prototype[name] = func
}

CodeMirror.fromTextArea = fromTextArea

addLegacyProps(CodeMirror)

CodeMirror.version = '5.49.2'
window.CodeMirror = CodeMirror
export default CodeMirror
